Current concepts in the rehabilitation of an acute rupture of the tendo Achillis

Whip-Lock Stitch Is Biomechanically Superior to Whipstitch for Semitendinosus Tendons

Purpose

To assess the biomechanical performance of different stitching methods using a suturing device by comparing the elongation, stiffness, failure load, and time to stitch completion in cadaveric semitendinosus tendons (STs) and quadriceps tendons (QTs).

Methods

A total of 24 STs and 16 QTs were harvested from cadaveric knee specimens (N = 40). Samples were randomly divided into 2 groups: whipstitch (WS) and whip-lock (WL) stitch. Both tendon ends were clamped to a graft preparation stand, and a 2-part needle was used to place 5 stitches, each 0.5 cm apart. Stitching time was recorded. Samples were preconditioned and then underwent cyclic loading from 50 to 200 N at 1 Hz for 500 cycles, followed by load-to-failure testing at 20 mm/min. Stiffness (in newtons per millimeter), ultimate failure load (in newtons), peak-to-peak displacement (in millimeters), elongation (in millimeters), and failure displacement (in millimeters) were recorded.

Results

Completion of the WS was significantly faster than the WL stitch in the ST (P < .001) and QT (P = .004). For the ST, the WL stitch exhibited higher ultimate failure loads and construct stiffness than the WS. Regarding the QT, the WL stitch showed higher stiffness and displacement than the WS; however, the ultimate failure load was higher for the WS in the QT. The ultimate failure load in the QT was higher than that in the ST for both stitches. In the ST, only 25% of WSs and 100% of WL stitches failed due to suture breakage. In the QT, suture breakage led to the failure of 100% of both the WL stitches and WSs.

Conclusions

In the ST, the WL stitch resulted in improved biomechanical performance through higher ultimate load and fewer failures from tissue damage compared with the WS. In the QT, both the WS and the WL stitch showed similar biomechanical performance with ultimate failure loads above established clinical failure thresholds.

Clinical Relevance

Various types of ligament and tendon injuries require suturing to enable repair or reconstruction. The success of ligament or tendon surgery often relies on soft-tissue quality. It is important to investigate the biomechanical properties of stitching techniques that help preserve soft-tissue quality as a step to determining their clinical suitability.

The Significance of Proprioceptive Training in the Post-Operative Rehabilitation of Patients Undergoing Achilles Tendon Reconstruction

In the human anatomy, the Achilles tendon (AT) is the strongest and largest tendon. Also, it ruptures the most often. Because it impairs the patient's ability to function adequately, a ruptured AT injury is a serious clinical issue. Reconstruction of the tendon through surgical intervention is the preferred approach to treatment in the case of tendon rupture. Establishing an effective post-operative rehabilitation regimen that mostly consists of functional physiotherapy measures is crucial in the management of AT rupture. In this report, we have presented the case of an AT reconstruction patient who complained of pain in the ankle region, reduced strength and range of the ankle joint, and loss of proprioception. The tailor-made physiotherapy protocol was incorporated, which included strengthening exercises, proprioceptive retraining, cryotherapy, and ambulatory training, which were found to be effective in facilitating early functional recovery.

Biomechanical comparison of shoelace suture technique for repairing calcaneal tendon

BACKGROUND

The biomechanical assessment of tendon repair is essential for the evaluation of different tendon suturing techniques. The shoelace suture technique with absorbable Vicryl® is a modified technique of Achilles tendon repair that may have biomechanical advantages depending on the number of threads used and the direction of the suture.

PURPOSE

To evaluate the creep under constant pre-load, the stiffness, the maximum strength, and the failure mode for three different configurations of the shoelace suture in a bovine tendon biomechanical model.

STUDY DESIGN

Controlled Laboratory Study.

METHODS

36 bovine Achilles tendon specimens were acquired and divided into three test groups of 12 Achilles tendons each. A model of the calcaneal tendon rupture was created through a transverse cut with a scalpel, performed 5 centimeters proximal to the calcaneal bone insertion. Group 1 was repaired using the simple shoelace technique with just one suture. Group 2 was repaired using the shoelace technique with three sutures individually sutured from distal to proximal at the site of rupture. Group 3 was repaired using the shoelace technique with three sutures individually sutured from proximal to distal at the site of rupture.

RESULTS

System creep after constant pre-load was 5.9 ± 2.5 mm, 3.0 ± 0.4 mm and 2.9 ± 0.4 mm for groups 1, 2 and 3, respectively. The system's stiffness was 23.2 ± 2.8 N/mm, 30.3 ± 1.1 N/mm and 29.8 ± 2.3 N/mm for groups 1, 2 and 3, respectively. In the final load-to-failure test, the ultimate load force (ULF) was 158.2 ± 27.5 N, 346.5 ± 47.6 N and 358.1 ± 41.6 N for groups 1, 2 and 3, respectively. There was statistical significance in the comparative tests between groups 1-2 and 1-3 in terms of means of creep, system stiffness and maximum system strength. No statistically significant difference was found between groups 2 and 3 when analyzing creep, system stiffness and ULF. Suture breakage was the prevalent mode of failure for all tested groups.

CONCLUSION

The shoelace with three sutures significantly reduced creep in the preloading phase and increased the stiffness and ultimate load force. The biomechanical results demonstrate better overall mechanical performance of the technique than the simple shoelace technique. The better mechanical performance indicates that the shoelace with three sutures could result in early postoperative rehabilitation.

CLINICAL RELEVANCE

This study indicates that the shoelace suture technique with three sutures is biomechanically strong and stiff, being a possible therapeutic option to be used.

Biomechanical Comparison of a Novel Multiplanar, Perpendicular Whipstitch With the Krackow Stitch and Standard Commercial Whipstitch

Background:

Using alternating orthogonal suture throws with the looped whipstitch technique may allow enhanced suture fixation.

Hypothesis:

It was hypothesized that this novel multiplanar, perpendicular looped whipstitch (MP) technique would have improved biomechanical properties compared with the standard looped whipstitch (WS) and Krackow stitch (KS).

Study Design:

Controlled laboratory study.

Methods:

A total of 30 cadaveric tibialis anterior tendons were randomly assigned into 3 groups of 10. Tendons were secured to a custom clamp, and the other end was sutured using 1 of 3 techniques: the KS, WS, or novel MP. The MP was performed with alternating orthogonal throws starting right to left, then front to back, left to right, and back to front. Each technique used 4 passes of No. 2 FiberWire spaced 5 mm apart and ending 10 mm from the tendon end. Tendons were preloaded to 5 N, pretensioned to 50 N at 100 mm/min for 3 cycles, returned to 5 N for 1 minute, cycled from 5 to 100 N at 200 mm/min for 100 cycles, and then loaded to failure at 20 mm/min. Elongation was recorded after pretensioning and cycling and was measured both across the suture-tendon interface and from the base of the suture-tendon interface to markings on the suture limbs (construct elongation). One-way analyses of variance were performed, with Bonferroni post hoc analysis when appropriate.

Results:

There were no differences in cross-sectional area or stiffness among the 3 techniques. The ultimate load for WS (183.33 ± 57.44 N) was less compared with both MP (270.76 ± 39.36 N) and KS (298.90 ± 25.94 N) (P ≤ .001 for both). There was less construct elongation for KS compared with WS and MP for total displacement, measured from pretensioning to the end of cycling (P < .001). All 3 techniques saw a decrease in length (shortening) at the suture-tendon interface during testing. There was more shortening at the suture-tendon interface for WS compared with KS (P = .006).

Conclusion:

The KS appears superior, as it maximized strength while minimizing construct elongation or graft shortening. The ultimate load of the MP technique was greater than that of the standard technique but not significantly different from that of the KS technique.

Clinical Relevance:

The KS is preferred. If using a WS, multiplanar, perpendicular passes should be considered.

The reliability, reproducibility and utilization of the radiographic Achilles Tendon Loading Angle in the management of Achilles Tendon rupture

BACKGROUND

During management of Achilles tendon rupture, determination of tendon-end approximation, either clinically or by ultrasound is difficult, following brace application of during loading. The Radiographic Achilles Tendon Loading Angle (RadATLA) is proposed as a method of measuring ankle position whilst loading in a brace during the management of Achilles tendon rupture. This study aims to determine the reliability and reproducibility of the RadATLA.

METHODS

A loaded true lateral ankle radiograph including the fifth metatarsal head was taken when wearing a brace at the 6-week time point in 18 patients (19 ankles). following Achilles tendon repair or reconstruction. The RadATLA was compared with the Tibio-talar angle, other radiographic and clinical measures used to quantify foot and ankle position during the first 6 weeks of early rehabilitation in a resting position and during loading.

RESULTS

The intra-rater reliability of both angles was found to be good (>0.8). The RadATLA was found to have an excellent intra-rater reliability with Intra-class correlation of (ICC) 0.992-0.996 (95%CI 0.889-0.999), standard error of the measurement (SEM) 1.03-3.65 and Minimal Detectable Change (MDC) 2.86-10.12. The inter-rater reliability was good with ICC of 0.798-0.969 (95%CI-0.03 to 0.964), SEM 2.9-7.6, and MDC 8.1-20.9. The RadATLA loaded at 6 weeks in all patients was at mean (SD) (range) 41.9˚ (16.5), (18.5-75.9). There was a significant difference between the patients in the Repair group compared with patients in the Reconstruction group both in RadATLA loaded at 6 weeks: 35.6˚ (11.2), (18.5-56.5) versus 55.5˚ (19), (20-75.9), (p = 0.01). The amount loaded in all patients was at mean (SD) (range) 29.2Kg (17.7), (2-56) and the percentage Body Weight was 30.7% (19), (2.1-63.2). There were no differences between the groups neither in amount loaded nor in percentage Body weight (p = 0.614-0.651).

CONCLUSIONS

The RadATLA is a reliable and reproducible angle and can be used to determine the position of the ankle, when loaded in a brace during rehabilitation following Achilles tendon rupture.

Plaster cast versus functional bracing for Achilles tendon rupture: the UKSTAR RCT

BACKGROUND

Achilles tendon rupture affects > 11,000 people each year in the UK, leading to prolonged periods away from work, sports and social activities. Traditionally, the ruptured tendon is held still in a plaster cast for ≥ 8 weeks. Functional bracing is an alternative treatment that allows patients to mobilise earlier, but there is little evidence about how bracing affects patients' recovery.

OBJECTIVES

To measure the Achilles Tendon Rupture Score, quality of life, complications and resource use of patients receiving non-operative treatment for an Achilles tendon rupture treated with plaster cast compared with those treated with functional bracing.

DESIGN

This was a multicentre, randomised, pragmatic, two-group superiority trial.

SETTING

The setting was 39 NHS hospitals.

PARTICIPANTS

A total of 540 adult patients treated non-operatively for Achilles tendon rupture were randomised from July 2016 to May 2018. Exclusion criteria included presenting after 14 days, having had previous rupture and being unable to complete questionnaires.

INTERVENTIONS

A total of 266 participants had a plaster cast applied, with their toes initially pointing to the floor. The cast was changed over 8 weeks to bring the foot into a walking position. A total of 274 patients had a functional brace that facilitated immediate weight-bearing. The foot position was adjusted within the brace over the same 8-week period.

MAIN OUTCOME MEASURES

Achilles Tendon Rupture Score is patient reported and assesses symptoms and physical activity related to the Achilles tendon (score 0-100, with 100 being the best possible outcome). The secondary outcomes were quality of life, complications and resource use at 8 weeks and at 3, 6 and 9 months.

RESULTS

Participants had a mean age of 48.7 years, were predominantly male (79%) and had ruptured their tendon during sports (70%). Over 93% of participants completed follow-up. There was no statistically significant difference in Achilles Tendon Rupture Score at 9 months post injury (-1.38, 95% confidence interval -4.9 to 2.1). There was a statistically significant difference in Achilles Tendon Rupture Score at 8 weeks post injury in favour of the functional brace group (5.53, 95% confidence interval 2.0 to 9.1), but not at 3 or 6 months post injury. Quality of life showed the same pattern, with a statistically significant difference at 8 weeks post injury but not at later time points. Complication profiles were similar in both groups. Re-rupture of the tendon occurred 17 times in the plaster cast group and 13 times in the functional brace group. There was no difference in resource use.

CONCLUSIONS

This trial provides strong evidence that early weight-bearing in a functional brace provides similar outcomes to traditional plaster casting and is safe for patients receiving non-operative treatment of Achilles tendon rupture. The probability that functional bracing is cost-effective exceeds 95% for the base-case imputed analysis, assuming a cost-effectiveness threshold of £20,000 per quality-adjusted life-year. On average, functional brace is associated with lower costs (-£103, 95% confidence interval -£290 to £84) and more quality-adjusted life-years (0.015, 95% confidence interval -0.0013 to 0.030) than plaster cast.

LIMITATIONS

Some patients declined to participate in the trial, but only a small proportion of these declined because they had a preference for one treatment or another. Overall, 58% of eligible patients agreed to participate, so the participants are broadly representative of the population under investigation.

FUTURE WORK

Although the UK Study of Tendo Achilles Rehabilitation provides guidance with regard to early management, rehabilitation following Achilles tendon rupture is prolonged and further research is required to define the optimal mode of rehabilitation after the initial cast/brace has been removed.

TRIAL REGISTRATION

Current Controlled Trials ISRCTN62639639.

FUNDING

This project was funded by the National Institute for Health Research (NIHR) Health Technology Assessment programme and will be published in full in Health Technology Assessment; Vol. 24, No. 8. See the NIHR Journals Library website for further project information.

Duration of immobilisation after Achilles tendon rupture repair by open surgery: a retrospective cohort study

Background

The best treatment for acute Achilles tendon ruptures remains controversial. No cohort studies have compared different immobilisation durations after open surgery. This retrospective cohort study aimed to determine the optimal duration of immobilisation after this surgery.

Methods

A total of 266 patients with acute Achilles tendon rupture were divided into 4 groups (A, B, C, and D) according to immobilisation duration of 0, 2, 4, and 6 weeks, respectively. All patients underwent the same suture technique with a similar rehabilitation protocol and were examined clinically at 2, 4, 6, 8, 10, 12, 14, 16, 24, and 48 weeks, with a final follow-up at a mean of 22.3 months postoperatively. The primary outcome was the time of return to light sports activity (LSA). Secondary outcomes included range of motion (ROM) and single-legged heel rise height (SHRH). Data on operation time, complications, visual analogue pain scale (VAS), American Orthopaedic Foot and Ankle Society (AOFAS) hindfoot score, and Achilles tendon Total Rupture score (ATRS) were also collected. Demographic baseline data were analysed using one-way analysis of variance; outcome parameters were analysed using Kruskal-Wallis H test, and complications were analysed using Fisher’s exact test. Statistical significance was considered at P ≤ 0.05.

Results

VAS scores decreased significantly, reaching 0 in all groups after 12 weeks. The AOFAS and ATRS scores were significantly different between the groups from weeks 2 to 12 (P<0.001) and weeks 2 to 16 (P<0.001), respectively. All the mean scores showed better results in group B than in the other groups. In terms of recovery time of ROM, SHRH, and LSA, groups A and B were significantly faster than groups C and D (P<0.001). There were 13 (13/266, 4.9%) complications: 5 superficial infections, 3 deep venous thrombosis, and 5 trauma-related re-ruptures. On the last follow-up, all complications had recovered. There were no significant differences in complications between the groups.

Conclusions

Immobilisation for 2 weeks after this open surgery is the best choice for early rehabilitation and weight-bearing while minimising pain and other complications.

Outcomes of Surgical Repair Versus Primary Tenodesis for Proximal Rectus Femoris Avulsion Injuries in Professional Athletes

BACKGROUND

Surgical repair of proximal rectus femoris avulsion injuries is associated with prolonged periods of rehabilitation and highly variable risk of injury recurrence. Surgical tenodesis of these injuries is often reserved for recurrent injuries or revision surgery. To our knowledge, the outcomes of proximal rectus femoris avulsion injuries treated with surgical repair versus primary tenodesis have not been previously reported.

HYPOTHESIS

Primary tenodesis of proximal rectus femoris avulsion injuries is associated with reduced risk of injury recurrence as compared with surgical repair.

STUDY DESIGN

Cohort study; Level of evidence, 3.

METHODS

This study included 25 patients (22 male and 3 female) who underwent surgical repair versus 30 patients (26 male and 4 female) who received primary tenodesis for proximal rectus femoris avulsion injuries. Predefined outcomes were recorded at regular intervals after surgery. Mean follow-up time was 27.9 months (range, 24.0-31.7 months) from date of surgery.

RESULTS

All patients returned to their preinjury levels of sporting activity. Primary tenodesis was associated with earlier return to preinjury level of sporting function as compared with surgical repair (mean ± SD, 12.4 ± 1.6 vs 15.8 ± 2.2 weeks; P < .001) and reduced risk of recurrence (0% vs 16%; P < .001). At 1-year follow-up, there was no difference in surgical repair versus primary tenodesis relating to patient satisfaction scores (12 very satisfied and 13 satisfied vs 16 very satisfied and 14 satisfied; P = .70), isometric quadriceps strength (95.6% ± 2.8% vs 95.2% ± 6.3%; P = .31), Tegner scores (median [interquartile range], 9 [8-9] vs 9 [8-9]; P = .54), and lower extremity functional scores (73 [72-76] vs 74 [72-75]; P = .41). High patient satisfaction, quadriceps muscle strength, and functional outcome scores were maintained and remained comparable between treatment groups at 2-year follow-up.

CONCLUSION

Primary tenodesis was associated with reduced time for return to preinjury level of sporting function and decreased risk of injury recurrence when compared with surgical repair for proximal rectus femoris avulsion injuries. There were no differences in patient satisfaction, functional outcome scores, and quadriceps muscle strength between the treatment groups at 1- and 2-year follow-up.

Systematic Review of Nonoperative Functional Protocols for Acute Achilles Ruptures Utilizing a Formal Rehabilitation Protocol Showing Lowest Rerupture Rates

AIM

To lay out a comprehensive protocol for practitioners and physical therapists that has the lowest rerupture rates for nonoperative treatment of acute Achilles ruptures.

METHOD

Relevant articles were searched in PubMed, CINAHL Plus, and Cochrane Library using keyword combinations: nonoperative AND/OR Achilles rupture AND functional AND/OR protocol or functional AND/OR rehabilitation. To be included in the full analysis, the studies had to have detailed functional protocols with physical therapy program details and outcome scores of rupture rates and/or Achilles Tendon Rupture Score (ATRS). We ultimately found 7 articles that fit our inclusion criteria for analysis. All of them had rerupture rates, and 4 had ATRS scores and functional protocols with mention of formal physical therapy programs.

RESULTS

Lowest rerupture rates were found in strict functional rehabilitation protocols that were full weightbearing in boot immediately at full equinus or 30° plantar flexed. They started active range of motion at 5 to 8 weeks and started formal physical therapy at 10 weeks.Levels of Evidence: Level III: Evidence obtained from well-designed non-experimental descriptive studies.

Musculotendinous Junction Injuries of the Proximal Biceps Femoris: A Prospective Study of 64 Patients Treated Surgically

BACKGROUND

Injuries to the hamstring complex most commonly involve the proximal musculotendinous junction of the long head of the biceps femoris (MTJ-BFlh). Nonoperative management of these injuries is associated with prolonged rehabilitation and high risk of recurrence. To our knowledge, the surgical management of acute MTJ-BFlh injuries has not been previously reported.

HYPOTHESIS

Surgical repair of acute MTJ-BFlh injuries enables return to sporting activity with low risk of recurrence.

STUDY DESIGN

Case series; Level of evidence, 4.

METHODS

A total of 64 patients (42 male and 22 female) undergoing surgical repair of acute MTJ-BFlh injuries were included. Predefined outcomes were recorded at regular intervals after surgery. Mean follow-up time after surgery was 29.2 months (range, 24.0-37.1 months).

RESULTS

All study patients returned to their preinjury levels of sporting activity. Mean ± SD time from surgical intervention to return to sporting activity was 13.4 ± 5.1 weeks. Three patients had reinjury at the operative site: 1 (1.6%) with MTJ-BFlh injury and 2 (3.2%) with myofascial tears. At 3 months after surgery, patients had improved mean passive straight-leg raise (72.0° ± 11.4° vs 24.1° ± 6.8°; P < .001); increased mean isometric hamstring muscle strength at 0° (84.5 % ± 10.4% vs 25.9% ± 8.9%; P < .001), 15° (89.5% ± 7.3% vs 41.2% ± 9.7%; P < .001), and 45° (93.9% ± 5.1% vs 63.4% ± 7.6%; P < .001); higher mean Lower Extremity Functional Scale scores (71.5 ± 5.0 vs 29.8 ± 6.3; P < .001); and improved mean Marx activity rating scores (9.8 ± 2.2 vs 3.8 ± 1.9; P < .001), as compared with preoperative scores. High patient satisfaction and functional outcome scores were maintained at 1 and 2 years after surgery.

CONCLUSION

Surgical repair of acute MTJ-BFlh injuries enables return to preinjury level of sporting function with low risk of recurrence at short-term follow-up.

Comparison Between Early Functional Rehabilitation and Cast Immobilization After Minimally Invasive Repair for an Acute Achilles Tendon Rupture

The purpose of the present study was to compare the outcomes of patients with Achilles tendon rupture treated with minimally invasive repair and early functional rehabilitation with the outcomes of similar patients treated with cast immobilization. After undergoing minimally invasive surgery, a below-knee splint with the foot in 30° of plantarflexion was applied to each patient for the first week. Patients were then assigned to a cast immobilization group (IG; n = 25) or a functional group (FG; n = 16). Data were collected during outpatient checks at 6 weeks, 3 months, 6 months, and 1 year. Outcomes of interest included range of motion (ROM), heel height, calf circumference, pain and functional score, return to work and light sports activity, and complications. The time interval for return to work in the FG was faster than that in the IG (p = .026). There was no clinically important difference between the 2 groups with regard to heel height, ROM, return to sports, calf circumference, visual analog scale, American Orthopaedic Foot and Ankle Society score, or Achilles tendon Total Rupture Score at every outpatient check except ROM difference at 6 weeks and heel height at 3 months. Rerupture occurred in 2 patients (1 [4%] in the IG and 1 [6.25%] in the FG). Early functional rehabilitation seemed to be as safe as traditional postoperative immobilization with a similar functional result and complications, but it was advantageous for the early phase of rehabilitation only.

Predictors of functional outcome in non-operatively managed Achilles tendon ruptures

BACKGROUND

Acute Achilles tendon (AT) rupture management remains debatable but non-operative functional regimes are beginning to gain popularity. The aim of this study was to identify predictors of functional outcome in patients with AT ruptures treated non-operatively with an immediate weight bearing functional regime in an orthosis.

METHODS

Analysis of prospectively gathered data from a local database of all patients treated non-operatively at our institution with an AT rupture was performed. For inclusion in the study patients required a completed Achilles Tendon Rupture Score (ATRS) at a minimum of 6 months post injury. The ATRS score was correlated against age, gender, time following rupture, duration (8 or 11 weeks) of treatment in a functional orthoses and complications were recorded.

RESULTS

236 patients of average age 49.5 years were included. The mean ATRS on completion of rehabilitation was 74 points. The mean ATRS was significantly lower in the 37 females (65.8) as compared to the 199 males (75.6) (p=0.013). Age inversely affected ATRS with a Pearsons correlation of -0.2. There was no significant difference in the ATRS score when comparing the two different treatment regime durations. There were 12 episodes of VTE and 4 episodes of re-rupture. The ATRS does not change significantly after 6 months following rupture treatment completion.

CONCLUSION

Patients with AT ruptures treated non-operatively with a functional rehabilitation regime demonstrate comparable function to other non-surgical regimes with low re-rupture rates. Increasing age and female gender demonstrate inferior functional outcomes.

CLINICAL RELEVANCE

Females and increasing age predict poorer functional outcome in acute Achilles tendon ruptures managed in a dynamic full-weight bearing treatment regime.

A novel method for reducing gap formation in tendon repair

Background

This study investigates gap formation in tendon repair using a novel tensioning method.

Hypothesis

The novel stitch will demonstrate less gap formation than the other suture configurations tested.

Methods

Porcine tendons stitched with classic Krackow stitch configurations were compared to a Krackow stitch modified with a proximal Tension-Assist Loop. Each group was cyclically loaded followed by analysis of the tendon-suture construct for gap formation.

Results

The Tension-Assist Loop group produced significantly less gap formation than each of the other stitch groups.

Conclusion

Decreasing early gap formation may be beneficial in allowing early rehabilitation and range of motion.

Development of an accelerated functional rehabilitation protocol following minimal invasive Achilles tendon repair

PURPOSE

Surgical repair after acute Achilles tendon rupture leads to lower re-rupture rates than non-surgical treatment. After open repair, early functional rehabilitation improves outcome, but there are risks of infection and poor wound healing. Minimal invasive surgery reduces these risks; however, there are concerns about its stability. Consequently, physicians may have reservations about adopting functional rehabilitation. There is still no consensus about the post-operative treatment after minimal invasive repair. The aim of this study was to define the most effective and safe post-operative rehabilitation protocol following minimal invasive repair.

METHODS

A systematic literature search in Embase, MEDLINE and Cochrane Library for prospective trials reporting on early functional rehabilitation after minimal invasive repair was performed. Seven studies were included.

RESULTS

One randomized controlled trail, one prospective comparative and five prospective non-comparative studies were identified. Four studies performed full weight bearing, all demonstrating good functional results, an early return to work/sports and high satisfaction. One study allowed early mobilization leading to excellent subjective and objective results. The only randomized controlled trial performed the most accelerated protocol demonstrating a superior functional outcome and fewer complications after immediate full weight bearing combined with free ankle mobilization. The non-comparative study reported high satisfaction, good functional results and an early return to work/sports following combined treatment.

CONCLUSION

Immediate weight bearing in a functional brace, together with early mobilization, is safe and has superior outcome following minimally invasive repair of Achilles tendon rupture. Our recommended treatment protocol provides quality assurance for the patient and reliability for the attending physician.

LEVEL OF EVIDENCE

II.

[Biomechanical study of different suture methods in repairing tendon rupture]

Objective

To evaluate the biomechanical property of tendons repaired with the modified Kessler suture combined with " 8" suture, and to provide evidence for the clinical application of this suture methods in repairing acute Achilles tendon rupture.

Methods

Forty frozen flexor digitorum longus tendons from fresh pork hind leg were randomly assigned into 4 groups, 10 specimens each group. In group A, the tendons were dissected transversely at the midpoint to forming the model of tendon with transversely cutting injury. The tendons in groups B, C, and D were dissected transversely at the midpoint, then a 2 cm segment of tendon from the incision in each side was dissected longitudinally with 1 mm internal to forming " frayed tendon" model. All the tendons were sutured with2-0 non-absorbable suture material with different suturing methods: in group A, the tendons with transversely cutting injury model with Krackow suture, and in the groups B, C, and D with Krackow suture, Kessler suture, and the modified Kessler suture combined with " 8" suture separately. All repaired tendons were fixed onto the biomechanical testing machine. The length, width, and thickness of each side and midpoint of the tendons were recorded, and the cross-sectional area was calculated. The tendons were stretched at a speed of 15 mm/minutes until failure (suture avulsion or rupture). The computer automatically recorded the maximum load, stress, strain, the failure displacement, and the stiffness. These biomechanical parameters of tendons in different groups were analyzed and compared.

Results

There was no significant difference in the length and cross-sectional area of each tendon among 4 groups ( F=0.245, P=0.863; F=0.094, P=0.963). Two tendons in group B, 1 in group C, and 1 in group D were excluded because of tendon slipping; all tendons in group A and 8 tendons in group B failured due to suture rupture, 9 tendons in group C due to suture slipping, and 9 tendons in group D due to 3 sutures slipping from tendon tissue together. The maximum load, the maximum stress, the maximum strain, the failure displacement, and the stiffness of the tendons between groups A and B showed no significant difference ( P>0.05). The maximum load, the maximum stress, and the stiffness of the tendons in group D were larger than those in both groups B and C ( P<0.05), but no significant difference was found in the maximum strain and the failure displacement between groups B, C, and D ( P>0.05). The maximum load, the maximum stress, the failure displacement, and the stiffness of the tendons in group B were larger than those in group C ( P<0.05), but the difference of maximum strain between groups B and C was not significant ( P>0.05).

Conclusion

The modified Kessler suture combined with " 8" suture can provide better biomechanical property of the repaired tendon compared with other suture approaches.

Semitendinosus Tendon for ACL Reconstruction: Regrowth and Mechanical Property Recovery

Background:

Semitendinosus/gracilis (STG) tendon autograft has been used effectively for restoring knee stability after anterior cruciate ligament (ACL) rupture. Though ACL reconstruction with STG autograft is an effective surgical technique for return to sports, short-term hamstring strength asymmetries exist after surgery. Although imaging evidence has demonstrated regrowth and reorganization of the semitendinosus (ST) tendon, no studies show whether the regrowth is associated with residual muscle function. Continuous shear wave elastography (cSWE) using an external actuator and high–frame rate ultrasound is a promising technique for evaluating the mechanical properties of regrown tendons in vivo.

Purpose:

To demonstrate recovery of the mechanical properties of the hamstring tendons after ACL reconstruction using an STG tendon autograft.

Study Design:

Case series; Level of evidence, 4.

Methods:

Thirteen patients underwent an STG autograft reconstruction after ACL rupture. Regrowth of the ST tendon was confirmed via b-mode ultrasound between 6 and 24 months postreconstruction. The shear elastic (µ₁) and viscosity moduli (µ₂) of the ST tendons were ascertained through cSWE using an external actuator and high–frame rate ultrasound.

Results:

Significant differences in both shear elastic (129.4 vs 73.0 kPa) and viscous moduli (192.6 vs 114.3 Pa·s) existed bilaterally for uninvolved and involved limbs, respectively. Additionally, a positive correlation between time postoperative and shear elasticity was observed (r = 0.60). More than 12 months were required for patients to regain a large percentage of the tendon’s mechanical properties compared with the contralateral side (µ₁, 80.6% at >12 months vs 39.9%; µ₂, 78.7% at >12 months vs 46.0%).

Conclusion:

The imaging and elastography data demonstrate tendon regrowth and recovery of functional biomechanical properties with time. The elastic modulus of the recovered tendon indicates the ability to transmit muscle force across the joint and recovery of semitendinosus function after its use for an ACL graft.

Interlocking horizontal mattress suture versus Kakiuchi technique in repair of Achilles tendon rupture: a biomechanical study

BACKGROUND

In recent years, the type of surgical treatment for Achilles tendon rupture has been the subject of controversial debate. This biomechanical study evaluates for the first time in literature the ultimate failure load (UFL) of interlocking horizontal mattress (IHM) suture as compared with Kakiuchi suture in Achilles tendon rupture. The hypothesis is that IHM suture can be performed also for Achilles tendon rupture and ensures higher resistance compared with the traditional Kakiuchi suture.

MATERIALS AND METHODS

Twenty fresh bovine Achilles tendons were obtained. Ten preparations were randomly assigned to each of two different groups: group A (10 specimens) sutured by IHM technique, and group B (10 specimens) sutured by Kakiuchi technique. Each construct was mounted and fixed on a tensile testing machine. Static preconditioning of 50 N was applied for 5 min as initial tensioning to stabilize the mechanical properties of the graft, then a load to failure test was performed at crosshead speed of 500 mm/min.

RESULTS

Ten specimens were tested for each group. The mean UFL was 228.6 ± 98.6 N in the IHM suture group and 96.57 ± 80.1 N in the Kakiuchi suture group. Statistical analysis showed a significant difference (p < 0.05) with better UFL in the IHM group. In both groups, the failure mode registered in each specimen was suture breakage (rupture of suture thread).

CONCLUSIONS

IHM suture achieved better UFL compared with Kakiuchi suture in an animal model of Achilles tendon repair. These results seem to support IHM as a valid option in Achilles tendon rupture.

Efficacy of repair techniques of the Achilles tendon: A meta-analysis of human cadaveric biomechanical studies

PURPOSE

Achilles injuries are very common, mainly among young athletes. When indicated, the surgical treatment aims for strong repairs that can resist distraction and consequently ruptures. The majority of the published clinical meta-analyses reported comparisons between broad treatment modalities such as conservative treatment, open, and minimally invasive surgery.

METHODS

A meta-analysis has been conducted to assess further clinical and biomechanical variables on human cadavers related to the efficacy of Achilles repair. A total of 26 studies with 596 legs met the inclusion criteria. The maximal load to failure was set as the primary outcome. Eleven studies were amenable to meta-analysis.

RESULTS

In the reinsertion group, the analysis of the single row vs. double row subgroup showed a significantly higher strength for the latter (1.27, 95% CI=0.748-1.806, I²=81%, P<0.0001). In the mid-tendon repair group, the Achillon vs. Krackow sutures and the Bunnell vs. Krackow sutures subgroups showed no difference while the Bunnell and Krakow sutures were significantly stronger than the Kessler sutures (0.96, 95% CI=0.510-1.405, I²=63.3%, P<0.0001 and 1.37, 95% CI=2.286-0.468, I²=83.4%, P=0.003; respectively).

CONCLUSIONS

The assessment of heterogeneity located variables such as age, suture/material type, number of strands, type of testing machine and software, preloading, ankle position and loading type as potential confounders. The results of this meta-analysis are likely to have a significant impact in clinical practice.

Early functional rehabilitation versus traditional immobilization for surgical Achilles tendon repair after acute rupture: a systematic review of overlapping meta-analyses

Several meta-analyses comparing early functional rehabilitation and traditional immobilization following surgical Achilles tendon repair after acute rupture have been published. However, they have led to conflicting conclusions. The aims of this systematic review were to select high-quality meta-analyses from multiple discordant meta-analyses and to provide a postoperative rehabilitation strategy following surgical repair using currently available evidence. We performed a comprehensive search using the PubMed and Embase databases and the Cochrane Library. Assessment of Multiple Systematic Reviews (AMSTAR) instrument was used to assess the methodological quality. Three investigators independently applied the Jadad decision algorithm. Their results were then compared to ensure selection of a meta-analysis that provided the highest quality of evidence. Six meta-analyses met the eligibility criteria. AMSTAR scores ranged from 6 to 10. According to the Jadad decision algorithm, a high-quality meta-analysis with a greater number of RCTs was selected. This meta-analysis showed that early functional rehabilitation was superior to cast immobilization in terms of patient satisfaction and the time to return to pre-morbid sporting levels. There were no differences regarding major complications or the time before return to prior employment and sporting activity. Thus, we recommend early functional rehabilitation as the postoperative strategy for acute Achilles tendon ruptures.

The effect of platelet-rich plasma on Achilles tendon healing in a rabbit model

OBJECTIVE

The aim of the present study was to evaluate the effects of PRP on Achilles tendon healing in rabbits during the inflammatory, proliferative, and remodeling phases by histological examination and quantitative assessments.

METHODS

Fifty mature male Japanese albino rabbits with severed Achilles tendons were divided into two equal groups and treated with platelet-rich plasma (PRP) or left untreated. Tendon tissue was harvested at 1, 2, 3, 4, and 6 weeks after treatment, and sections were stained with hematoxylin-eosin and monoclonal antibodies against CD31 and type I collagen.

RESULTS

Collagen fibers proliferated more densely early after severance, and subsequent remodeling of the collagen fibers and approximation of normal tendinous tissue occurred earlier in the PRP group than in the control group. The fibroblast number was significantly higher in the PRP group than in the control group at 1 and 2 weeks. Similarly, the area ratio of CD31-positive cells was significantly higher in the PRP group than in the control group at 1 and 2 weeks. Positive staining for type I collagen was more intense in the PRP group than in the control group after 3 weeks, indicating tendon maturation.

CONCLUSION

Administration of PRP shortened the inflammatory phase and promoted tendon healing during the proliferative phase.

Non-surgical treatment of Achilles rupture: Does duration in functional weight bearing orthosis matter?

BACKGROUND

The treatment of acute Achilles tendon ruptures is continually being debated. The success of non-surgical regimes is now evident yet there remains a high rate of surgery in the United States of America and Scandinavia. Recent studies have investigated functional outcome rather than complication rates as primary outcome but the current data are still sparse. We aimed to investigate whether there is any difference in functional outcomes between two dynamic regimes of differing durations for acute Achilles tendon ruptures.

METHODS

The patients in the two groups were matched for age, gender, follow-up duration and mechanism of injury. Forty-four patients were managed in a regime of 11 weeks and another 44 patients for 8 weeks. Demographics, injury details, complications and functional outcome were recorded. The validated Achilles Tendon Rupture Score (ATRS) was used to assess functional outcomes. Minimum follow-up was 1 year.

RESULTS

The 11-week group had a mean age of 50.8 years (range: 27-80) with 36 (82%) males. The 8-week group had a mean age of 52.0 years (range: 32-77) with 36 (82%) males. The mean ATRS for the 11-week group was 76.0 (range: 8-100). The mean ATRS for the 8-week group was 76.1 (range: 30-100). There were no re-ruptures in the 11-week group and one in the 8-week group. There were three episodes of venous thromboembolism in the 11-week group and four in the 8-week group.

CONCLUSION

A reduction in duration of dynamic rehabilitation for non-operative treatment of Achilles tendon rupture from 11 weeks to 8 weeks does not lead to a significant detriment in functional outcomes or complication rates.

Efficacy of early controlled motion of the ankle compared with no motion after non-operative treatment of an acute Achilles tendon rupture: study protocol for a randomized controlled trial

BACKGROUND

Early controlled ankle motion is widely used in the non-operative treatment of acute Achilles tendon rupture, though its safety and efficacy have never been investigated in a randomized setup. The objectives of this study are to investigate if early controlled motion of the ankle affects functional and patient-reported outcomes.

METHODS/DESIGN

The study is performed as a blinded, randomized, controlled trial with patients allocated in a 1:1 ratio to one of two parallel groups. Patients aged from 18 to 70 years are eligible for inclusion. The intervention group performs early controlled motion of the ankle in weeks 3-8 after rupture. The control group is immobilized. In total, 130 patients will be included from one big orthopedic center over a period of 2½ years. The primary outcome is the patient-reported Achilles tendon Total Rupture Score evaluated at 12 months post-injury. Secondary outcome measures are the heel-rise work test, Achilles tendon elongation, and the rate of re-rupture. The primary analysis will be conducted as intention-to-treat analyses.

DISCUSSION

This trial is the first to investigate the safety and efficacy of early controlled motion in the treatment of acute Achilles tendon rupture in a randomized setup. The study uses the patient-reported outcome measure, the Achilles tendon Total Rupture Score, as the primary endpoint, as it is believed to be the best surrogate measure for the tendon's actual capability to function in everyday life.

TRIAL REGISTRATION

ClinicalTrials.gov: NCT02015364 . Registered on 13 December 2013.

Biomechanical comparison of three methods for distal Achilles tendon reconstruction

PURPOSE

To compare the load at failure and stiffness associated with three surgical techniques for distal Achilles tendon reconstruction (AT).

METHODS

Nine matched pairs of fresh-frozen human cadaveric ATs were divided into three groups. Distal AT reconstruction was performed using suture anchors or one of two lengths of tendon overlap (10 or 5 mm). Each tendon was loaded to failure. The load at failure (N), stiffness (N/mm), and mode of failure were recorded. Differences in load at failure and stiffness were analysed.

RESULTS

Mean load at failure was significantly higher in the 10-mm group than in the 5-mm group (p < 0.05) or the suture-anchor group (p < 0.05). Load at failure did not differ significantly between the suture-anchor and 5-mm group, and stiffness did not differ significantly between any two groups. In the 10- and 5-mm groups, failure was caused by the grafts pulling out through the substance of the AT. Modes of failure varied in the suture-anchor group.

CONCLUSIONS

The load at failure was higher in the 10-mm group than in the 5-mm and suture-anchor groups. Although all three surgical techniques provide sufficient primary load-bearing ability, the 10-mm tendon-overlap technique may be more conducive to early post-operative rehabilitation.

Surgical Management of Recurrent Musculotendinous Hamstring Injury in Professional Athletes

BACKGROUND

Hamstring injury is the most common muscular lesion in athletes. The conservative treatment is well described, and surgical management is often indicated for proximal tendinous avulsions. To our knowledge, no surgical treatment has been proposed for failure of conservative treatment in musculotendinous hamstring lesions.

PURPOSE

To describe the surgical management of proximal and distal hamstring musculotendinous junction lesions in professional athletes after failure of conservative treatment.

STUDY DESIGN

Case series; Level of evidence, 4.

METHODS

A consecutive series of 10 professional athletes, including 4 soccer players, 4 rugby players, and 2 handball players, underwent surgical intervention between October 2010 and June 2014 for the treatment of recurrent musculotendinous hamstring injuries. All athletes had failed at least 3 months of conservative treatment for a recurrent musculotendinous hamstring injury. Surgical resection of the musculotendinous scar tissue was performed using a longitudinal muscular suture. Lower Extremity Functional Scale (LEFS) and Marx scores were obtained at the 3-month follow-up, and a final phone interview was completed to determine recurrence of hamstring injury and return to previous level of play.

RESULTS

The mean age at surgery was 25.2 years (range, 19-35 years). The musculotendinous hamstring lesions involved 8 semitendinosus and 2 biceps femoris, with 6 injuries located proximally and 4 distally. Conservative treatment lasted a mean 5.1 months (range, 3-9 months) after last recurrence, and the patients had an average of 2.7 (range, 2-5) separate incidents of injury recurrence before surgical intervention was decided upon. At the 3-month follow-up, all patients had Marx activity scores of 16 and LEFS scores of 80. All 10 patients returned to the same level of play at a mean 3.4 months (range, 2-5 months). At a mean follow-up of 28.7 months, none of the athletes had suffered a recurrence. No surgical complication was encountered.

CONCLUSION

In cases of failed conservative treatment of musculotendinous hamstring lesions, surgical intervention may be a viable treatment option in professional athletes and allows the patient to return to the same level of play.

Percutaneous, Minimally Invasive Repair of Traumatic and Simultaneous Rupture of Both Achilles Tendons: A Case Report

Achilles injury is a common musculoskeletal disorder. Bilateral rupture of the Achilles tendon, however, is much less common and usually occurs spontaneously. Complete, traumatic, and bilateral ruptures are rare and typically require long periods of immobilization before the patient can return to full weightbearing. A 52-year-old male was hospitalized for bilateral traumatic rupture to both Achilles tendons. No risk factors for tendon rupture were found. Blood samples revealed no peripheral blood pathologic features. Both tendons were repaired with percutaneous, minimally invasive surgery using the Achillon(®) tendon suture system. Rehabilitation was begun 4 weeks later. An ankle-foot orthosis was prescribed to provide ankle support with an adjustable range of movement, and active plantar flexion was set at 0° to 30°. The patient remained non-weightbearing with the ankle-foot orthosis device and performed active range-of-motion exercises. At 8 weeks after surgery, we recommended that he begin walking with partial weightbearing using a foot-tibial orthosis with the range of motion set to 45° plantar flexion and 15° dorsiflexion. At 10 weeks postoperatively, he was encouraged to return to full weightbearing on both feet. Beginning rehabilitation as soon as possible after minimally invasive surgery, compared with 6 weeks of immobilization after surgery, provided a rapid resumption to full weightbearing. We emphasize the clinical importance of a safe, simple treatment program that can be followed for a patient with damage to the Achilles tendons. To our knowledge, ours is the first report of minimally invasive repair of bilateral simultaneous traumatic rupture of the Achilles tendon.

Intermittent pneumatic compression reduces the risk of deep vein thrombosis during post-operative lower limb immobilisation

Deep vein thrombosis is a common complication of immobilising the lower limb after surgery. We hypothesised that intermittent pneumatic compression (IPC) therapy in outpatients who had undergone surgical repair of acute ruptures of the Achilles tendon could reduce the incidence of this problem.

A total of 150 patients who had undergone surgical repair of the Achilles tendon were randomised to either treatment with IPC for six hours per day (n = 74) under an orthosis or treatment as usual (n = 74) in a plaster cast without IPC. At two weeks post-operatively, the incidence of deep vein thrombosis was assessed using blinded, double-reported compression duplex ultrasound. At this point, IPC was discontinued and all patients were immobilised in an orthosis for a further four weeks. At six weeks post-operatively, a second compression duplex ultrasound scan was performed.

At two weeks, the incidence of deep vein thrombosis was 21% in the treated group and 37% in the control group (p = 0.042). Age over 39 years was found to be a strong risk factor for deep vein thrombosis (odds ratio (OR) = 4.84, 95% confidence interval (CI) 2.14 to 10.96). Treatment with IPC, corrected for age differences between groups, reduced the risk of deep vein thrombosis at the two-week point (OR = 2.60; 95% CI 1.15 to 5.91; p =0.022). At six weeks, the incidence of deep vein thrombosis was 52% in the treated group and 48% in the control group (OR 0.94, 95% CI 0.49 to 1.83). IPC appears to be an effective method of reducing the risk of deep vein thrombosis in the early stages of post-operative immobilisation of outpatients. Further research is necessary to elucidate whether it can confer similar benefits over longer periods of immobilisation and in a more heterogeneous group of patients.

Cite this article: Bone Joint J 2015;97-B:675–80.

Rehabilitation regimen after surgical treatment of acute Achilles tendon ruptures: a systematic review with meta-analysis

BACKGROUND

The choice of rehabilitation management after the surgical repair of acute Achilles tendon (AT) ruptures remains controversial because of insufficient clinical evidence. The current study analyzes the postoperative rehabilitation of AT ruptures based on the current clinical evidence.

PURPOSE

To identify and analyze the high-level clinical evidence regarding postoperative rehabilitation after the surgical repair of AT ruptures. Subgroup analyses were also performed to obtain more reliable and specific results.

STUDY DESIGN

Meta-analysis.

METHODS

The studies were retrieved by searching the Medline, Embase, and Cochrane databases through the OVID retrieval engine from 1990 to August 14, 2013. Two independent reviewers critically reviewed the studies using preset inclusion and exclusion criteria. The quality of the eligible studies was assessed by the Cochrane 12-item scale. All included studies were summarized, and their data were extracted. Subgroup analyses were performed according to the different protocols of early functional rehabilitation.

RESULTS

Nine studies, consisting of 6 randomized controlled trials and 3 quasi-randomized studies, were ultimately included. A total of 402 patients were identified. Six of the included studies utilized early weightbearing combined with early ankle motion exercises, while the other 3 only employed early ankle motion exercises. The subgroup analyses demonstrated that 11 of the 15 functional outcome measurements were significantly superior for patients who underwent both early weightbearing and ankle motion exercises than for those who underwent conventional cast immobilization. Similar rates of reruptures (odds ratio [OR], 1.36; 95% CI, 0.38-4.91; P = .64) and major complications (OR, 0.67; 95% CI, 0.24-1.87; P = .44) as well as a significantly lower rate of minor complications (OR, 0.51; 95% CI, 0.27-0.95; P = .03) were also observed in this early functional rehabilitation group. For the patients who solely performed early ankle motion exercises, only 2 of the 14 functional measurements were observed to be significantly superior to immobilization. There were also no significant differences in the rates of reruptures (OR, 0.47; 95% CI, 0.08-2.70; P = .40) and other complications (OR, 1.09; 95% CI, 0.41-2.92; P = .86) between the 2 groups.

CONCLUSION

Postoperative early weightbearing combined with early ankle motion exercises is associated with a lower minor complication rate and achieves superior and more rapid functional recovery than conventional immobilization after surgical AT repair. In contrast, few advantages were identified when only early ankle motion exercises were applied.

Healing of human Achilles tendon ruptures: radiodensity reflects mechanical properties

PURPOSE

This study tests the idea of using radiodensity from computed tomography to quantitatively evaluate the healing of ruptured Achilles tendons.

METHODS

The radiodensity of the healing tendons in sixty-five patients who were treated for Achilles tendon rupture was measured. The hypothesis was that density would correlate with an estimate for e-modulus, derived from strain, measured by radiostereometry with different mechanical loadings.

RESULTS

Radiodensity 7 weeks after injury was decreased to 67 % (SD 11) of the contralateral, uninjured tendon. There was no improvement in radiodensity from 7 to 19 weeks, whereas at 1 year, it had increased to 106 % (SD 7). Only 2 of 52 measured values at 1 year were lower than the highest value at 19 weeks, i.e. there was minimal overlap. The variation in radiodensity could explain 80 % of the variation in e-modulus, but radiodensity correlated only weakly with e-modulus at each time point separately. At 1 year, both radiodensity and e-modulus correlated with functional results, although weakly.

CONCLUSIONS

From 19 weeks onwards, radiodensity appears to reflect mechanical properties of the tendon and might to some extent predict the final outcome. Radiodensity at 7 weeks is difficult to interpret, probably because it reflects both callus and damaged tissues.

Biomechanical comparison of Krackow locking stitch versus nonlocking loop stitch with varying number of throws

BACKGROUND

Common suture configuration techniques used for ligament and tendon grafts and repair are the Krackow locking stitch and a nonlocking loop stitch, such as a whipstitch. Clinically, the preferences of orthopaedic surgeons vary.

HYPOTHESIS

The Krackow locking stitch and the nonlocking whipstitch, with varying suture loops, produce different biomechanical and physical effects on the tendon end.

STUDY DESIGN

Controlled laboratory study.

METHODS

A total of 52 fresh-frozen porcine flexor digitorum tendons were used and assigned into 10 groups. Two stitch configurations (Krackow stitch [K] and whipstitch [W]) with varying number of loops (2 throws, n = 6; 4 throws, n = 5; 6 throws, n = 5; 8 throws, n = 5; 10 throws, n = 5) were tested. No. 2 FiberWire was used. Each sample was preloaded to 5 N and then cyclically loaded for 200 cycles to 200 N at 1 Hz, and then the tendon-suture construct was analyzed for gap formation, tendon elongation, and tendon end width. Next, each tendon was loaded to failure, and ultimate strength and mode of failure were recorded. Data were evaluated with 2-way analysis of variance.

RESULTS

For gap formation, the Krackow stitch produced less gap compared with the whipstitch (15.2 ± 4.0 mm [K] vs 18.9 ± 6.8 mm [W]; P = .012). Gap formation was larger when the number of loops increased from 2 to ≥6 (P = .015). For elongation, the Krackow technique increased the tendon length after cyclic loading. In contrast, the whipstitch was noted to shorten the length of the tendon (1.17 ± 0.97 mm [K] vs -0.14 ± 1.13 mm [W]; P < .001). For tendon end width, the Krackow better preserved the transverse width (-0.64 ± 0.81 mm [K] vs -1.39 ± 0.64 mm [W]; P = .001). Both stitch types had similar ultimate strength (322.1 ± 20.3 N [K] vs 319.7 ± 20.4 N [W]; P = .676) and modes of failure (all by suture breakage; therefore, no statistical calculation was performed). There was no statistical difference in tendon elongation, width, failure load, or mode regardless of the number of throws.

CONCLUSION/CLINICAL RELEVANCE

Given the finding that the Krackow suture had less gap formation and better preservation of tendon architecture (length and width) compared with the whipstitch, coupled with the finding that ultimate strength is similar with both types of sutures, the Krackow stitch is recommended for tendon reconstruction when these parameters are important.

Accelerated rehabilitation following Achilles tendon repair after acute rupture - Development of an evidence-based treatment protocol

The acute rupture of the Achilles tendon is a protracted injury. Surgery is only the beginning of a long rehabilitation period. Therefore, the rehabilitation protocol is an integral aspect to restore the pre-injury activity level. Despite several trials available comparing different treatment regimes, there is still no consensus regarding the optimal protocol. Consequently, the aim of our study was to systematically search the evidence available and define a precise rehabilitation programme after operative repair of acute Achilles tendon rupture based on the trials with the highest level of evidence. We performed a systematic literature search in Medline, Embase and Cochrane library. We identified twelve randomized controlled trials comparing different treatment regimes after operative repair of the Achilles tendon. Five trials compared full to non weight bearing, all applying immobilization in equinus. Immediate full weight bearing led to significant higher patient satisfaction, earlier ambulation and return to pre-injury activity. Four trials compared early ankle mobilization to immobilization. All trials found mobilization to be superior as it shortens time to return to work and sports significantly. Three trials compared the combination of full weight bearing and early ankle mobilization to immobilization. This combination was most beneficial. Patients showed significantly higher satisfaction, less use of rehabilitation resources, earlier return to pre-injury activities and further demonstrated significantly increased calf muscle strength, reduced atrophy and tendon elongation. No study found an increased rerupture rate for the more progressive treatment. In conclusion, the rehabilitation protocol after Achilles tendon repair should allow immediate full weight bearing. After the second postoperative week controlled ankle mobilization by free plantar flexion and limited dorsiflexion at 0° should be applied.

Tendon and ligament regeneration and repair: clinical relevance and developmental paradigm

As dense connective tissues connecting bone to muscle and bone to bone, respectively, tendon and ligament (T/L) arise from the somitic mesoderm, originating in a recently discovered somitic compartment, the syndetome. Inductive signals from the adjacent sclerotome and myotome upregulate expression of Scleraxis, a key transcription factor for tenogenic and ligamentogenic differentiation. Understanding T/L development is critical to establishing a knowledge base for improving the healing and repair of T/L injuries, a high-burden disease due to the intrinsically poor natural healing response. Current treatment of the three most common tendon injuries-tearing of the rotator cuff of the shoulder, flexor tendon of the hand, and Achilles tendon-include mostly surgical repair and/or conservative approaches, including biophysical modalities such as rehabilitation and cryotherapy. Unfortunately, the fibrovascular scar formed during healing possesses inferior mechanical and biochemical properties, resulting in compromised tissue functionality. Regenerative approaches have sought to augment the injured tissue with cells, scaffolds, bioactive agents, and mechanical stimulation to improve the natural healing response. The key challenges in restoring full T/L function following injury include optimal combination of these biological agents as well as their delivery to the injury site. A greater understanding of the molecular mechanisms involved in T/L development and natural healing, coupled with the capability of producing complex biomaterials to deliver multiple biofactors with high spatiotemporal resolution and specificity, should lead to regenerative procedures that more closely recapitulate T/L morphogenesis, thereby offering future patients the prospect of T/L regeneration, as opposed to simple tissue repair.

A novel repair method for the treatment of acute Achilles tendon rupture with minimally invasive approach using button implant: a biomechanical study

BACKGROUND

Minimally invasive Q3 repair has been proposed for acute Achilles tendon rupture with low rate of complications. However there are still controversies about optimal technique. In this study we aimed to describe Endobutton-assisted modified Bunnell configuration as a new Achilles tendon repair technique and evaluate its biomechanical properties comparing with native tendon and Krackow technique.

METHODS

27 ovine Achilles tendons were obtained and randomly placed into 3 groups with 9 specimens ineach. The Achilles tendons were repaired with Endobutton-assisted modified Bunnell technique in group 1, Krackow suture technique in group 2 and group 3 was defined as the control group including native tendons. Unidirectional tensile loading to failure was performed at 25mm/min. Biomechanicalproperties such as peak force to failure (N), stress at peak (MPa), elongation at failure, and Young'smodulus (GPa) was measured for each group. All groups were compared with each other using one-wayANOVA followed by the Tukey HSD multiple comparison test (a=0.05).

RESULTS

The average peak force (N) to failure of group 1 and group 2 and control group was 415.6±57.6, 268.1±65.2 and 704.5±85.8, respectively. There was no statistically significant difference between native tendon and group 1 for the amount elongation at failure (p>0.05).

CONCLUSIONS

Regarding the results, we concluded that Endobutton-assisted modified Bunnell technique provides stronger fixation than conventional techniques. It may allow early range of motion and can be easily applied in minimally invasive and percutaneous methods particularly for cases with poor quality tendon at the distal part of rupture.

LEVEL OF EVIDENCE

Level II, Biomechanical research study.

Achilles tendon ruptures

The incidence of acute Achilles tendon ruptures is on the rise. This is thought to be due to the increasing number of middle-aged persons participating in athletic and/or strenuous activity. Ruptures of the Achilles tendon can be severely debilitating, with deficits seen years after the initial incident. Also, these injuries can have substantial socioeconomic impacts regardless of the treatment selected. Debate continues over the optimal treatment of Achilles tendon ruptures, especially the argument whether to treat patients nonoperatively or surgically. Newer evidence shows that functional rehabilitation, including early weight-bearing, should be an integral part of successful treatment of acute Achilles ruptures. Further research is needed to further investigate the ideal treatment and rehabilitation protocols.

Can foot compression under a plaster cast prevent deep-vein thrombosis during lower limb immobilisation?

We hypothesised that adjuvant intermittent pneumatic compression (IPC) beneath a plaster cast would reduce the risk of deep-vein thrombosis (DVT) during post-operative immobilisation of the lower limb. Of 87 patients with acute tendo Achillis (TA) rupture, 26 were prospectively randomised post-operatively after open TA repair. The treatment group (n = 14) received two weeks of IPC of the foot for at least six hours daily under a plaster cast. The control group (n = 12) had no additional treatment. At two weeks post-operatively all patients received an orthosis until follow-up at six weeks. At two and six weeks the incidence of DVT was assessed using colour duplex sonography by two ultrasonographers blinded to the treatment. Two patients withdrew from the study due to inability to tolerate IPC treatment. An interim analysis demonstrated a high incidence of DVT in both the IPC group (9 of 12, 75%) and the controls (6 of 12, 50%) (p = 0.18). No significant differences in incidence were detected at two (p = 0.33) or six weeks (p = 0.08) post-operatively. Malfunction of the IPC leading to a second plaster cast was found to correlate with an increased DVT risk at two weeks (ϕ = 0.71; p = 0.019), leading to a premature abandonment of the study. We cannot recommend adjuvant treatment with foot IPC under a plaster cast for outpatient DVT prevention during post-operative immobilisation, owing to a high incidence of DVT related to malfunctioning of this type of IPC application.

Surgical repair of the ruptured Achilles tendon: the cost-effectiveness of open versus percutaneous repair

PURPOSE

Recent meta-analyses have shown reduced re-rupture rates for the surgical management of Achilles ruptures. However, percutaneous repair has been demonstrated to lead to improved function and patient satisfaction but greater complications than open repair. In the current economic climate, it is reasonable to consider the financial cost of rupture management for both the patient and the provider. The cost-effectiveness of operative treatment of ruptures of the Achilles tendon was determined based upon theatre occupancy, clinic attendance and cast changes, operative complications and functional assessment score.

METHODS

The cost-effectiveness of the surgical management of Achilles tendon ruptures between 2005 and 2011 in our unit was audited by comparing 49 patients receiving percutaneous repair to 35 patients whom had open repairs.

RESULTS

There was no significant difference in complications between the two surgical techniques: (Open vs. Percutaneous) overall rates 14.3 versus 10.4 %: infection; 2.7 versus 2.0 %, transient sural nerve damage: 5.6 versus 8.1 %, wound breakdown: 2.8 versus 0.0 %, re-rupture: 2.8 versus 2.0 %. Achilles Total Rupture Scores (ATRS) were comparable [Open 89 (65-100) at 49 months vs. Percutaneous 88.8 (33-100) at 12 months (n.s.)]. Theatre occupancy (P < 0.00) and hospital stay (P < 0.00) were significantly longer with open repair [43 min (26-70) and 2.9 days (0-4)] compared to percutaneous repair [15 min (12-43) and 1.2 days (0-2)]. Excluding the costs of running the operating theatre, we have estimated the costs of surgery for open repair to be £ 935 and percutaneous repair to be £ 574.

CONCLUSIONS

This study suggests that percutaneous repair of the Achilles tendon resulted in reduced costs and yet had comparable outcome and complications rates to open repair in surgical management of the Achilles tendon. Percutaneous repair should be considered as the primary method of cost-effective surgical management of Achilles tendon rupture.

Return to competitive play after hamstring injuries involving disruption of the central tendon

BACKGROUND

The hamstring muscles are the most commonly injured muscle group in many different sports. Recovery time is often unpredictable and prolonged, and recurrent injury is common.

HYPOTHESIS

Hamstring injuries that disrupt the central tendon enclosed within the muscle belly require a longer recovery time than do injuries involving only muscle, epimysial fascia, or the musculotendinous junction.

STUDY DESIGN

Cohort study; Level of evidence, 3.

METHODS

Injury records from professional sports teams were reviewed to determine the length of recovery from each hamstring injury that occurred over a 24-month period. The integrity of the central tendon on magnetic resonance imaging (MRI) was retrospectively reviewed for each case. The association between central tendon disruption on MRI and recovery time was determined.

RESULTS

There were 62 hamstring injuries included for analysis; 45 (72%) involved the biceps femoris, 11 (18%) involved the semimembranosus, and 6 (10%) involved the semitendinosus. Central tendon disruption was identified in 12 (45%) of the biceps femoris injuries and in none of the injuries to the other 2 muscles. Three of these injuries were treated surgically, with a median recovery time of 91 days. The median (interquartile range [IQR]) recovery times for those remaining biceps femoris injuries with and without central tendon disruption were 21 days (IQR, 9-28) and 72 days (IQR, 42-109), respectively (P < .01).

CONCLUSION

Disruption of the central tendon in injuries to the biceps femoris results in a significantly longer recovery time than injuries that do not disrupt the central tendon. This highlights the distinction between injury to the hamstring muscle and injury to the hamstring tendon, which is underappreciated as being a distinct entity when injury involves the enclosed central portion of the tendon.

Normal aging alters in vivo passive biomechanical response of the rat gastrocnemius-Achilles muscle-tendon unit

Predisposition to Achilles tendon (AT) ruptures in middle-aged individuals may be associated with age-related changes to inherent passive biomechanical properties of the gastrocnemius-Achilles (GC-AT) muscle-tendon unit, due to known muscle-tendon structural changes in normal aging. The goal of this study was to determine whether the passive biomechanical response of the GC-AT muscle-tendon unit was altered with age in 6 young (8 months) and 6 middle-aged (24 months) F344xBN hybrid rats from the National Institute on Aging colony. Fung's quasilinear viscoelastic (QLV) model was used to determine in vivo history and time-dependent load-relaxation response of the GC-AT. Effective stiffness and modulus were also estimated using linear regression analysis. Fung's QLV revealed a significantly decreased magnitude of the relaxation response (parameter C, p=0.026) in middle-aged animals compared to young animals (0.108±0.007 vs. 0.144±0.015), with similar time-dependent viscous GC-AT properties (τ(1), τ(2)). The product of elastic parameters (A*B), which represents the initial slope of the elastic response, was significantly increased by 50% in middle-aged rats (p=0.014). Estimated GC-AT stiffness increased 28% at peak tensions in middle-aged rats (2.7±0.2 N/mm) compared to young rats (1.9±0.2 N/mm; p=0.036). While the limitations of this animal model must be considered, the changes we describe could be associated with the observation that GC-AT pathology and injury is more common in middle-aged individuals. Further studies are necessary to characterize the load-to-failure behavior of AT in middle-aged compared to young animals.

Biomechanical comparison of four methods of repair of the Achilles tendon

We tested four types of surgical repair for load to failure and distraction in a bovine model of Achilles tendon repair. A total of 20 fresh bovine Achilles tendons were divided transversely 4 cm proximal to the calcaneal insertion and randomly repaired using the Dresden technique, a Krackow suture, a triple-strand Dresden technique or a modified oblique Dresden technique, all using a Fiberwire suture. Each tendon was loaded to failure. The force applied when a 5 mm gap was formed, peak load to failure, and mechanism of failure were recorded. The resistance to distraction was significantly greater for the triple technique (mean 246.1 N (205 to 309) to initial gapping) than for the Dresden (mean 180 N (152 to 208); p = 0.012) and the Krackow repairs (mean 101 N (78 to 112; p < 0.001). Peak load to failure was significantly greater for the triple-strand repair (mean 675 N (453 to 749)) than for the Dresden (mean 327.8 N (238 to 406); p < 0.001), Krackow (mean 223.6 N (210 to 252); p <  0.001) and oblique repairs (mean 437.2 N (372 to 526); p < 0.001). Failure of the tendon was the mechanism of failure for all specimens except for the tendons sutured using the Krackow technique, where the failure occurred at the knot.

The triple-strand technique significantly increased the tensile strength (p = 0.0001) and gap resistance (p = 0.01) of bovine tendon repairs, and might have advantages in human application for accelerated post-operative rehabilitation.