Isokinetic Plantar Flexion Research Articles

Conservative treatment outcome for Achilles tendon re-rupture occurring in the subacute phase after primary repair.

Until now, a treatment protocol for Achilles tendon re-rupture (ATRR) occurring in the postoperative period 5-12weeks following primary Achilles tendon repair has not been established. We refer to this time frame as the subacute postoperative phase, and the objective of this study was to assess the efficacy of conservative treatment for subacute ATRR in this phase. We conducted a retrospective review of 390 cases (385 patients) who had undergone primary Achilles tendon repair using the 4-strand Krachow method between January 2010 and August 2021. All patients were subjected to more than 12months of follow-up and were categorized into two groups based on the presence of subacute ATRR: Group 1 comprised 370 cases without ATRR, while Group 2 comprised 20 cases with ATRR. Following confirmation of ATRR, we immediately applied a below-knee cast in an ankle plantar flexed position (25°-30°), followed by bracing according to the same rehabilitation plan used for the primary repair. After administering conservative treatment to the patients with ATRR, we compared several outcome parameters between the two groups, including isokinetic plantar flexion power measured using a dynamometer, time required for a single heel raise (t-SHR), time needed for ten repetitive SHRs (t-SHR10), Achilles Tendon Total Rupture Score (ATRS), and Foot and Ankle Ability Measure (FAAM) scores. The baseline timepoints for Groups 1 and 2 were the dates of the primary repair and the re-injury event. After primary Achilles tendon repair, subacute ATRR occurred in 5.1% of patients. There were no significant differences between the groups in terms of t-SHR and t-SHR10 (P = 0.281, 0.486). Similarly, the isokinetic dynamometer measurements revealed no significant differences in peak torque for plantar flexion at angular velocities of 30°/s and 120°/s, both in absolute values and as a percentage of the contralateral side, between the groups (P > 0.05 for each). However, ATRSs were significantly lower in Group 2 compared to Group 1 before 6months (P < 0.05), as were FAAM-Activities of Daily Living scores at 6months (P < 0.05). After 12months, there were no significant differences in these scores between the two groups (both P > 0.05). Conservative treatment for subacute ATRR following primary Achilles tendon repair yields clinical outcomes comparable to those without ATRR. Therefore, we recommend that surgeons consider relying on the patient's natural healing capabilities rather than opting for aggressive surgical interventions, as expediting such operations may be unnecessary for subacute injuries.

Combined effect of contraction type and intensity on corticomuscular coherence during isokinetic plantar flexions.

During isometric contractions, corticomuscular coherence (CMC) may be modulated along with the contraction intensity. Furthermore, CMC may also vary between contraction types due to the contribution of spinal inhibitory mechanisms. However, the interaction between the effect of the contraction intensity and of the contraction type on CMC remains hitherto unknown. Therefore, CMC and spinal excitability modulations were compared during submaximal isometric, shortening and lengthening contractions of plantar flexor muscles at 25, 50, and 70% of the maximal soleus (SOL) EMG activity. CMC was computed in the time-frequency domain between the Cz EEG electrode signal and the SOL or medial gastrocnemius (MG) EMG signals. The results indicated that beta-band CMC was decreased in the SOL only between 25 and 50-70% contractions for both isometric and anisometric contractions, but remained similar for all contraction intensities in the MG. Spinal excitability was similar for all contraction intensities in both muscles. Meanwhile a divergence of the EEG and the EMG signals mean frequency was observed only in the SOL and only between 25 and 50-70% contractions, independently from the contraction type. Collectively, these findings confirm an effect of the contraction intensity on beta-band CMC, although it was only measured in the SOL, between low-level and high-level contraction intensities. Furthermore, the current findings provide new evidence that the observed modulations of beta-band CMC with the contraction intensity does not depend on the contraction type or on spinal excitability variations.

Absorbable versus nonabsorbable sutures for the Krackow suture repair of acute Achilles tendon rupture: a prospective randomized controlled trial.

Although absorbable sutures for the repair of acute Achilles tendon rupture (ATR) have been attracting attention, the rationale for their use remains insufficient. This study prospectively compared the outcomes of absorbable and nonabsorbable sutures for the repair of acute ATR. A total of 40 patients were randomly assigned to either braided absorbable polyglactin suture or braided nonabsorbable polyethylene terephthalate suture groups. ATR was then repaired using the Krackow suture method. At three and six months after surgery, the isokinetic muscle strength of ankle plantar flexion was measured using a computer-based Cybex dynamometer. At six and 12 months after surgery, patient-reported outcomes were measured using the Achilles tendon Total Rupture Score (ATRS), visual analogue scale for pain (VAS pain), and EuroQoL five-dimension health questionnaire (EQ-5D). Overall, 37 patients completed 12 months of follow-up. No difference was observed between the two groups in terms of isokinetic plantar flexion strength, ATRS, VAS pain, or EQ-5D. No re-rupture was observed in either group. The use of absorbable sutures for the repair of acute ATR was not inferior to that of nonabsorbable sutures. This finding suggests that absorbable sutures can be considered for the repair of acute ATRs. Cite this article: Bone Joint J2022;104-B(8):938-945.

Effect of plyometric training on dynamic leg strength and jumping performance in rhythmic gymnastics: A preliminary study

BACKGROUND: Reactive performance is an important component of rhythmic gymnastics. So far, it is unclear whether additional plyometric training in female gymnasts shows an increase in performance. OBJECTIVE: The aim of the study was to examine the effect of additional plyometric training in rhythmic gymnastics on the reactive jumping performance and strength of the lower leg muscles. METHODS: Fifteen rhythmic gymnasts (age: 12.3 ± 2.6 years, height: 1.47 ± 0.12 m, body weight: 37.3 ± 9.3 kg, BMI: 16.7 ± 2.1 kg*m-2; competition level: national and international championships, Tanner stages I–III) participated in the study. The athletes were assigned to an experimental (EG) and a control group (CG). The EG performed plyometric exercises three times per week in addition to the regular training. Before and after six weeks of training the reactive jump performance, the work of dorsi flexors and plantar flexors performed during isokinetic plantarflexion, as well as the performance in two sport-specific tests were measured. RESULTS: In contrast to the CG, in the EG the jump height (pre: 24.8; post: 27.25 cm; p&lt; 0.05) and the reactive-strength-index (pre: 1.01; post: 1.19; p&lt; 0.01) increased significantly. The EG achieved significant improvements in the counter movement jump test (pre: 27.0 cm; post: 31.5 cm; p&lt; 0.01) and in the sport specific double rope jump test (jumps per minute, pre: 18.0; post: 23.0; p&lt; 0.01). Furthermore, a significant increase in work performed during plantarflexion was found in the EG for the right leg (pre: 24.9 J; post: 29.7 J; p&lt; 0.01) and a tendency to increase for the left leg (pre: 26.4 J; post: 37.7 J; p= 0.05). CONCLUSION: Both reactive strength and dynamic force can be efficiently increased by plyometric training. It may be recommended to include plyometric exercises in the training regime of rhythmic gymnasts.

Stretch-Shortening Cycle Performance and Muscle-Tendon Properties in Dancers and Runners.

The purpose of this investigation was to elucidate whether ankle joint stretch-shortening cycle performance, isometric and isokinetic plantarflexion strength, and maximal Achilles tendon force and elongation differ between dancers, endurance runners, and untrained controls. To differentiate between dancers, endurance runners, and controls, the authors measured maximal Achilles tendon force and elongation during isometric ramp contractions with ultrasonic imaging, maximal isometric and isokinetic plantarflexion strength with dynamometry, and stretch-shortening cycle function during countermovement hopping and 30-cm drop hopping with a custom-designed sled. The Achilles tendon of dancers elongated significantly (P ≤ .05) more than runners and controls. Dancers were significantly stronger than controls during isometric contractions at different ankle angles. Concentric and eccentric strength during isokinetic contractions at 60°·s-1 and 120°·s-1 was significantly higher in dancers and runners than controls. Dancers hopped significantly higher than runners and controls during hopping tasks. Dancers also possessed significantly greater countermovement hop relative peak power, drop hop relative impulse, and drop hop relative peak power than controls. Finally, dancers reached significantly greater velocities during countermovement hops than runners and controls. Our findings suggest dancing and running require or likely enhance plantarflexion strength. Furthermore, dancing appears to require and enhance ankle joint stretch-shortening cycle performance and tendon elongation.

Isokinetic Plantar Flexion Endurance. Reliability and Validity of output/excitation Measurements

The reliability and validity of isokinetic measurement of plantar flexion endurance has been studied by a method previously described by us which utilizes simultaneous measurements of mechanical contractional work (CW) and integrated electromyogram (iEMG). The reliability was gauged by test/re-test with a two year's interval; while validity was assessed by myoelectric power spectrum analyses. The output/input balance (CW/iEMG) remained unchanged for the group as well as inter-individually. Changes in myoelectric power spectrum as function of number of contractions were clearly indicative of fatigue. Under the present conditions fatigue of fast twitch motor units may explain the rapid decreases in output and excitation followed by nearly steady state levels of all registered parameters. As is the case for non-fatigued isokinetic plantar flexions, the motor unit recruitment order appears quite stereotyped during plantar flexion fatigue. The findings of significantly lower mean power spectrum during the first part of each contraction than during the second part may support the size-principle described by Henneman.

Morphological and functional outcomes of operatively treated Achilles tendon ruptures

ABSTRACT Objectives: Achilles tendon rupture leads to functional impairments and these may be underpinned by morphological changes in the muscle-tendon unit. The functional performance of the injured limb will be impaired regardless of time since surgery and these impairments occur alongside changes in muscle-tendon morphology. Methods: Following operative treatment of Achilles tendon rupture and short-term immobilization, 12 patients completed a battery of tests during a single visit to the laboratory (performed an average of 4.4 ± 2.6 years post-surgery). Patients completed the Achilles’ tendon rupture score (ATRS), tests of the ankle and hip range of motion (ROM) and ultrasound measurements of muscle-tendon architecture. Data on isokinetic (30°/s, 60°/s) plantar flexion strength, jumping performance and walking-running were also collected on the same visit. Percentage deficits were expressed relative to the non-injured limb and determined for statistical significance (p < 0.05). Relationships between outcome measures and time since surgery were tested using Pearson’s correlation coefficients (p < 0.05). Results: The repaired limb showed a shorter muscle fascicle length (12.1–19.6%), increased fascicle pennation (18.0 ± 22.14%) and reduced muscle thickness (9.1–20.1%) in the gastrocnemius and/or soleus along with greater tendon cross-sectional area (46.7 ± 34.47%). Functionally, the repaired limb displayed lower countermovement jump height (−12.6 ± 15.68%) and longer drop jump contact times (5.5 ± 5.7%). Also, the repaired limb showed reduced hip internal-external ROM (6.3 ± 8.2%) but no differences existed between limbs for plantar flexion ROM and strength or gait characteristics. Good ATRS outcomes were reported (mean: 87.9 ± 16.2, range: 43–100) which related to time since surgery (r = 0.79) but individual ATRS items did not correlate with corresponding objective measures. Conclusion: Plantar flexor atrophy following surgically treated Achilles tendon rupture is partially compensated for by remodeling of the fascicles; however, impairments may still persist many years into the postoperative period although these may be more pronounced in high-velocity activities.

Total Ankle Arthroplasty: Is Ankle Plantarflexion Strength Important?

Category:Ankle ArthritisIntroduction/Purpose:Ankle push off power, which requires gastroc-soleus muscle strength, is a critical aspect of healthy gait and increases as gait speed increases. It is therefore surprising that one-to-two-year outcomes following total ankle arthroplasty (TAA) include improved gait speed but deficient ankle power. One possible explanation for low ankle power following TAA is ankle plantarflexion weakness. Information on plantarflexion strength is extremely limited in people before or after TAA. Evaluating plantarflexion strength may inform postoperative expectations and guide rehabilitation programs. The purpose of this study was to evaluate the change in ankle plantarflexion strength, ankle power during gait, and gait speed before and after TAA in people with end-stage ankle arthritis, and in comparison to a healthy matched control group.Methods:Twenty-five participants were included in this prospective case-control study. TAA group participants (n = 13) [mean (SD): Age 60.9 (15.3) years; BMI 30.53 (5.5) Kg/m2; 85% male] with end-stage ankle arthritis who received a TAA were evaluated preoperatively and six months postoperatively. Performance of adjunct soft tissue procedures were patient specific (5/13 participants received tendo-achilles lengthening). All patients received formal physical therapy. Healthy control participants (n=12) were matched to the TAA group on age, gender and BMI. Ankle peak isokinetic plantarflexion strength (torque at 60 and 120 degrees/second; Nm/kg) was measured with an instrumented dynamometer. Peak ankle power (joint torque x segmental velocity; W/kg) was calculated via three-dimensional multi-segment foot motion analysis while participants walked barefoot over a force plate at controlled speeds. Gait speed (m/s) was measured with the Six-Minute Walk Test. Appropriate nonparametric comparisons were made to evaluate differences across time, between limbs, and between groups.Results:Compared to preoperative values, involved limb ankle strength was preserved at 60 and 120 degrees/second following TAA (both p > 0.59). Postoperative involved limb ankle strength at both speeds were 37-56% lower than the non-involved limb and control group (all p < 0.05) (Figure 1). Similarly, involved limb ankle power was preserved following TAA (p = 0.43), but remained at least 38% lower than the non-involved limb or control group (both p < .01). A subset analysis revealed that TAA participants with tendo-achilles lengthening had 25-33% less involved limb postoperative ankle power and strength than TAA participants without tendo-achilles lengthening. Interestingly, gait speed increased following TAA (p = 0.01) and was similar to control group speeds [TAA 1.5 vs. Control 1.6 m/s; p = 0.59].Conclusion:Robust improvements in gait speed were observed following TAA. These values approached normative gait speed in spite of diminished ankle strength and power. Ankle plantarflexion weakness reduces the capacity to generate ankle power during gait, regardless of possible contributing factors (i.e. preexisting atrophy/weakness, tendo-achilles lengthening). Accordingly, improvements in gait speed were likely linked to proximal joint compensations (i.e. hip, knee). The long term consequences of plantarflexion weakness may negatively affect implant loading. Study findings provide new information and point to the importance of targeting strength during postoperative TAA rehabilitation, potentially adjusting strategies for patients receiving soft tissue lengthening procedures.

Results of tenorrhaphy with early rehabilitation for acute tear of Achilles tendon.

For the treatment of acute Achilles tendon rupture, early rehabilitation after surgical repair is believed to be a useful method. The purpose of this study was to evaluate the outcome of open tenorrhaphy followed by early rehabilitation. A total of 112 patients who underwent open repair and early rehabilitation for acute Achilles tendon rupture from January 2003 to March 2015 were retrospectively reviewed. These 112 patients (80 men, 32 women) had an average age of 43.1 years (22-62 years), and the mean follow-up period was 91.8 months (12-171 months). A short leg cast was applied postoperatively for an average of 16.5 days (12-20 days). The mean duration of bracing was 6.9 weeks (6-8 weeks). Each patient was assessed based on range of motion, single heel raising test, calf circumference compared to the contralateral limb, ability to return to previous activity, the Arner-Lindholm scale, and the American orthopaedic foot and ankle society (AOFAS) hind foot scale. Isokinetic plantar flexion power was also checked. All patients were fully satisfied (AOFAS ≥ 90) with the treatment results, and 96 patients were able to return to their previous athletic activities. As assessed by the Arner-Lindholm scale, 103 cases were rated as excellent and the other 9 cases were rated as good. At the 1-year follow-up period, single heel raise and hopping was possible in every patient. Compared to the contralateral side, 10 subjects (8.9%) had minor limitation of dorsiflexion motion, and an average of 1.6 cm calf circumference difference without functional disabilities. There were no major complications such as re-rupture, nerve injury, or infection. For acute Achilles tendon ruptures, open surgical repair with optimal length restoration, followed by earlier rehabilitation results in good functional outcomes and a successful return to pre-injury levels of physical activity without major complications. Level IV.

Does Ankle Muscle Performance Mirror Improved Pain Following Total Ankle Arthroplasty?

Category: Ankle Arthritis Introduction/Purpose: Total ankle arthroplasty (TAA) outcomes include pain reduction and improved gait speed. Ankle push off power, which requires gastroc-soleus muscle strength, is a critical aspect of healthy gait and increases as gait speed increases. It appears that improvements in pain translate to improved ankle muscle performance. However, ankle power after TAA is surprisingly low. It is possible years of arthritis and latent muscle memory result in reduced gastroc-soleus muscle strength and a gait pattern reliant on proximal joints for power. Evaluating these hypotheses will drive postoperative care. The purpose of this ongoing prospective study is to be the first to evaluate the interplay of pain, gait speed, and ankle muscle performance (strength and power) in people following TAA for end-stage ankle arthritis. Methods: Twelve people [Mean (SD): Age 61 (14.3) years; BMI 30.0 (5.4) Kg/m2; 83% male] with end-stage ankle arthritis who were candidates for TAA participated (12 preoperative and 9 six-month postoperative visits). Performance of adjunct soft tissue procedures and postoperative care were patient specific. A twenty point numeric pain rating scale was used to measure worst pain in the past week. Three dimensional multi-segment foot motion analysis was performed while participants walked barefoot on level ground over a force plate. Ankle peak push-off power (joint torque x segmental velocity) was calculated. Ankle peak isokinetic plantarflexion strength (torque at 60 degrees / second) and ankle sagittal plane passive range of motion were measured with a dynamometer. Participants also completed the six minute walk test. Wilcoxon Signed Rank tests were used to evaluate preoperative to postoperative changes and between limb differences postoperatively. Results: Pain decreased (postoperative mean = 2.8; p = 0.01) and gait speed increased following TAA (p = 0.02). Ankle plantarflexion strength and ankle power during walking were preserved following TAA (both p &gt; 0.8) (Figure 1). Postoperative group mean dorsiflexion was 25.1 degrees and plantarflexion was 18.9 degrees, suggesting sufficient ankle motion was present for plantarflexor muscle performance. However, between limb differences were significant for both strength and power (both p &lt; 0.05) postoperatively. The involved ankle produced 36% less strength and generated 45% less power during walking in comparison to the uninvolved limb. This asymmetry demonstrates that involved limb ankle muscle performance was not normalized at six-month follow up, despite improvements in pain. Conclusion: Study findings provide preliminary evidence that improved pain and gait speed are disconnected from ankle muscle performance following TAA. Postoperative improvements in gait speed were likely driven by more proximal joints (i.e. hip). Without additional targeted postoperative plantarflexion strengthening and gait training to improve ankle muscle involvement, gains in ankle power, a symmetrical gait pattern, and patient tolerance to higher level activity (i.e. stairs) are unlikely to occur long-term. The underpinning mechanisms limiting the necessary strength to drive power generation (i.e. length-tension relationship, atrophy), and the possible cumulative effect of how abnormal gait may influence implant survivorship deserve further attention.

Tendon Length, Calf Muscle Atrophy, and Strength Deficit After Acute Achilles Tendon Rupture: Long-Term Follow-up of Patients in a Previous Study.

In this prospective study, we used magnetic resonance imaging (MRI) to assess long-term Achilles tendon length, calf muscle volume, and muscle fatty degeneration after surgery for acute Achilles tendon rupture. From 1998 to 2001, 60 patients at our center underwent surgery for acute Achilles tendon rupture followed by early functional postoperative rehabilitation. Fifty-five patients were reexamined after a minimum duration of follow-up of 13 years (mean, 14 years), and 52 of them were included in the present study. Outcome measures included Achilles tendon length, calf muscle volume, and fatty degeneration measured with MRI of both the affected and the uninjured leg. The isokinetic plantar flexion strength of both calves was measured and was correlated with the structural findings. The Achilles tendon was, on average, 12 mm (95% confidence interval [CI] = 8.6 to 15.6 mm; p < 0.001) longer (6% longer) in the affected leg than in the uninjured leg. The mean volumes of the soleus and medial and lateral gastrocnemius muscles were 63 cm (13%; p < 0.001), 30 cm (13%; p < 0.001), and 16 cm (11%; p < 0.001) lower in the affected leg than in the uninjured leg, whereas the mean volume of the flexor hallucis longus (FHL) was 5 cm (5%; p = 0.002) greater in the affected leg, indicating FHL compensatory hypertrophy. The median plantar flexion strength for the whole range of motion ranged from 12% to 18% less than that on the uninjured side. Finally, the side-to-side difference in Achilles tendon length correlated substantially with the strength deficit (ρ = 0.51, p < 0.001) and with medial gastrocnemius (ρ = 0.46, p = 0.001) and soleus (ρ = 0.42, p = 0.002) muscle atrophy. Increased Achilles tendon length is associated with smaller calf muscle volumes and persistent plantar flexion strength deficits after surgical repair of Achilles tendon rupture. Strength deficits and muscle volume deficits are partly compensated for by FHL hypertrophy, but 11% to 13% deficits in soleus and gastrocnemius muscle volumes and 12% to 18% deficits in plantar flexion strength persist even after long-term follow-up. Therapeutic Level II. See Instructions for Authors for a complete description of levels of evidence.

Effect of teeth clenching on isometric and isokinetic strength of ankle plantar flexion.

To investigate the effect of voluntary teeth clenching on the isometric and isokinetic exercises of the lower limbs, the association of muscle strength (peak torque, PT) and muscle activities (integrated electromyographic activity per unit of time, iEMG/s) of the three muscles of the triceps surae with teeth clenching during isometric and isokinetic plantar flexion were simultaneously measured for 12 healthy male volunteers using a Cybex 6000 Extremity Testing and Rehabilitation System and a surface EMG analyzing system. The statistical analysis demonstrated that for the isometric exercise, PT and each iEMG/s significantly increased in association with teeth clenching, and a positive correlation existed between the biting force and each variable. In contrast, no association was found with teeth clenching for the isokinetic exercise. In this study, therefore, it was found that the effect of teeth clenching differed between the isometric and isokinetic exercises.

Soleus Atrophy Is Common After the Nonsurgical Treatment of Acute Achilles Tendon Ruptures: A Randomized Clinical Trial Comparing Surgical and Nonsurgical Functional Treatments

Background: It remains controversial whether nonsurgical or surgical treatment provides better calf muscle strength recovery after an acute Achilles tendon rupture (ATR). Recent evidence has suggested that surgery might surpass nonsurgical treatment in restoring strength after an ATR. Purpose: To assess whether magnetic resonance imaging (MRI) findings could explain calf muscle strength deficits and the difference between nonsurgical and surgical treatments in restoring calf muscle strength. Study Design: Randomized controlled trial; Level of evidence, 1. Methods: From 2009 to 2013, 60 patients with acute ATRs were randomized to surgery or nonsurgical treatment with an identical rehabilitation protocol. The primary outcome measure was the volume of calf muscles assessed using MRI at 3 and 18 months. The secondary outcome measures included fatty degeneration of the calf muscles and length of the affected Achilles tendon. Additionally, isokinetic plantarflexion strength was measured in both legs. Results: At 3 months, the study groups showed no differences in muscle volumes or fatty degeneration. However, at 18 months, the mean differences between affected and healthy soleus muscle volumes were 83.2 cm3 (17.7%) after surgery and 115.5 cm3 (24.8%) after nonsurgical treatment (difference between means, 33.1 cm3; 95% CI, 1.3-65.0; P = .042). The study groups were not substantially different in the volumes or fatty degeneration of other muscles. From 3 to 18 months, compensatory hypertrophy was detected in the flexor hallucis longus (FHL) and deep flexors in both groups. In the nonsurgical treatment group, the mean difference between affected and healthy FHL muscle volumes was −9.3 cm3 (12%) and in the surgical treatment group was −8.4 cm3 (10%) (P ≤ .001). At 18 months, Achilles tendons were, on average, 19 mm longer in patients treated nonsurgically compared with patients treated surgically (P < .001). At 18 months, surgically treated patients demonstrated 10% to 18% greater strength results (P = .037). Calf muscle isokinetic strength deficits for the entire range of ankle motion correlated with soleus atrophy (ρ = 0.449-0.611; P < .001). Conclusion: Treating ATRs nonsurgically with a functional rehabilitation protocol resulted in greater soleus muscle atrophy compared with surgical treatment. The mean Achilles tendon length was 19 mm longer after nonsurgical treatment than after the surgical treatment of ATRs. These structural changes partly explained the 10% to 18% greater calf muscle strength observed in patients treated with surgery compared with those treated nonsurgically. Registration: NCT02012803 (ClinicalTrials.gov identifier).

Tendon Resection and Functional Rehabilitation for Achilles Tendon Infection Following Tendon Repair

Category: Other. Introduction/Purpose: An infected Achilles tendon after tendon repair is particularly difficult to treat because of the poor vascularity of the tendon, itself, as well as the thin surrounding soft tissue. For management of an infected Achilles tendon following tendon repair, we first focused on complete debridement with tenectomy and then promoted scar healing of the Achilles tendon using functional management. Methods: We retrospectively reviewed all of the medical records of 15 patients with post-operative infection of the Achilles tendon occurring between 2007 and 2012. The mean follow-up time was 33 months (range, twenty two to 97 months). Tenectomy with radical debridement was performed, and the ankle was placed in a short leg splint for two weeks. The splint was then replaced with an ankle brace for the next four weeks. Partial weight-bearing walking was allowed immediately, and full weight-bearing walking was allowed two weeks postoperatively. We assessed the physical parameters such as range of motion, the calf circumference, capability of single heel raising, satisfactions and the Arner Lindholm scale were recorded. Laboratory test, post- operative ultrasonography and isokinetic plantar flexion power was also checked. Results: At the final follow-up, any sign of infection had disappeared without recurrence in all of the patients. Achilles tendon continuity recovered in all by scar healing. Compared to the contralateral side, there was no difference in the range of motion in eight patients. According to the Arner Lindholm scale, nine of fifteen cases were excellent and the other six cases were good. Their ability regarding single-heel rising on involved leg was achieved in ten patients. Eleven of 15 patients could return to their pre-injury recreational activities. Diffuse homogeneous echotexture of the Achilles tendon with continuity within the tendon sheath was observed on the ultrasonographic examination or MRI. Conclusion: Tenectomy of infected Achilles tendon and radical debridement with vigorous rehabilitation is simple and successful management way for the postoperative infection following Achilles tendon repair.

Habitual Use of High-Heeled Shoes Affects Isokinetic Soleus Strength More Than Gastrocnemius in Healthy Young Females.

Habitual use of high-heeled shoes (HHS) has been reported to negatively impact different body structures. However, few studies have investigated its effect on plantarflexor performance. The aim of this study was to investigate the effect of habitual wear of HHS and knee joint position (to isolate the function of the gastrocnemius) on the isokinetic performance of the plantarflexors and ankle joint range of motion (ROM). A high-heel (HH) group included 12 women (25.4 ± 4.8 y) who have been wearing HHS for ≥40 hours/wk and for at least a year. A control group (CTRL) had 12 women (21.3 ± 0.5 y) who have occasionally been wearing HHS for <10 hours/wk. Participants performed isokinetic (60 degrees/s) plantarflexion movements through a range set between 15 degrees dorsiflexion and 30 degrees plantarflexion. Ankle joint ROM and average peak plantarflexion torque and power were recorded in 2 knee joint positions, extension and 90 degrees flexion. Overall, torque was significantly affected by knee position (P = .04) and habitual use of HHS (P < .001), whereas power was impacted by knee position only (P < .001). Within each group, flexing the knee reduced isokinetic measurements. However, the reduction was greater for the HH group (torque: 54 Nm, power: 35.6 W) compared with the CTRL group (torque: 42 Nm, power: 32.5 W). Ankle joint ROM was significantly different between groups in knee flexion only. Flexing the knee limited the plantarflexor muscular performance and the limitation was more significant in habitual users of HHS compared to nonusers. Thus, it is concluded that habitual use of HHS impacts the contractile properties of soleus more than gastrocnemius. The soleus is important for walking and anterior cruciate ligament protection. Thus, HHS users could be susceptible to injury and may need longer and more intensive posttraumatic rehabilitation. Therefore, clinicians should consider knee position when examining the plantarflexors of habitual HHS users.

Debridement and Functional Rehabilitation for Achilles Tendon Infection Following Tendon Repair.

An infected Achilles tendon after tendon repair is particularly difficult to treat because of the poor vascularity of the tendon as well as the thin surrounding soft tissue. For treatment of an infected Achilles tendon following tendon repair, we first focused on complete debridement and then promoted fibrous scar healing of the Achilles tendon using functional treatment. We retrospectively reviewed all of the medical records of 15 tertiary referral patients with postoperative infection of the Achilles tendon occurring between 2007 and 2012. The mean follow-up time was 33 months (range, 22 to 97 months). The infected tissue and the necrotic tendon were debrided, and the ankle was placed in a short leg splint for 2 weeks. The splint was then replaced with an ankle brace for the next 4 weeks. Partial weight-bearing was allowed immediately, and full weight-bearing was allowed at 2 weeks postoperatively. We assessed and recorded the physical parameters such as the range of motion, calf circumference, ability to perform a single-limb heel rise, patient satisfaction, and Arner-Lindholm scale. Laboratory tests, postoperative ultrasonography, and isokinetic plantar flexion power tests were also performed. At a mean time of 17 days (range, 8 to 30 days) after debridement, infection signs such as discharge from the wound, redness, and local warmth resolved. The wound had healed and the stitches were removed at a mean of 17 days following the wound repair. At the time of the latest follow-up, there were no signs of active infection. Achilles tendon continuity recovered in all patients by fibrous scar healing. Compared with the contralateral side, there was no difference in the ankle range of motion in 8 patients. According to the Arner-Lindholm scale, 9 of the 15 results were excellent and 6 were good. Ten patients were able to perform a single-limb heel rise. Eleven of 15 patients returned to their pre-injury recreational activities. Diffuse homogeneous echotexture of the Achilles tendon with continuity was observed on the ultrasonographic examination. In this retrospective series, radical debridement, combined with antibiotic therapy and functional rehabilitation, was successful in eradicating infection and maintaining function in patients with postoperative infection following Achilles tendon repair. Therapeutic Level IV. See Instructions for Authors for a complete description of levels of evidence.

Effects of Plyometric Training on Rock’n’Roll Performance

Objectives: The aim of the study was to analyse if plyometric training increases the sport specific performance in rock’n’roll dancers. Design: Fifteen semi-professional rock’n’roll dancers participated in a plyometric training study. Pre- and posttests were conducted to document alterations of sport specific performance, reactive strength as well as maximal isokinetic torque. Method: The participants (n=15) accomplished two training sessions weekly for a training period of 6 weeks. The training program consisted of different of jumps. Pre- and posttests included a rock’n’roll specific performance test examining the maximal number of kicks within 30 s. Moreover, jumping height and ground contact time (GCT) during drop jump were determined to calculate reactive strength (RSI). Maximal dynamic torque and work were determined during maximal isokinetic contractions of the plantar flexors. Results: The number of kicks increased from 46.5 ± 2.6 to 49.4 ± 2.7 (p=0.00, d Z =1.83).The RSI increased significantly from 2.57 ± 0.29 to 2.72 ± 0.44 (p=0.05, d Z =0.55). The gains of RSI are based on increases in jumping height (pretest: 24.6 ± 4.0 cm, posttest 26.5 ± 4.7 cm, p=0.01, d Z =0.71), whereas the GCT remained unaltered (p=0.53). The work during maximal isokinetic plantar flexions increased significantly in both legs (jumping leg: p = 0.04, d Z =0.58; kicking leg: p=0.05, d Z =0.55). Conclusions: Plyometric training increases the kicking frequency during rock’n’roll dance. This might be attributed to the observed increase in reactive strength. Training induced changes in muscle activity or structure were discussed. It is suggested to implement plyometric training into the training program of rock’n’roll dancers. Keywords: Rock’n’roll, plyometric training, reactive strength, plantar flexors

Early Functional Treatment Versus Cast Immobilization in Tension After Achilles Rupture Repair

Background: There are no long-term prospective controlled trials comparing postoperative regimens after Achilles tendon rupture repair. Purpose: To compare ≥10-year outcomes of 2 postoperative regimens after Achilles tendon rupture repair: early weightbearing with early mobilization versus early weightbearing with early immobilization in tension. Study Design: Randomized controlled trial; Level of evidence, 1. Methods: A total of 50 patients with acute Achilles tendon ruptures were randomized postoperatively to receive either early movement of the ankle between neutral and plantar flexion in a brace for 6 weeks (group 1) or Achilles tendon immobilization in tension using a below-knee cast with the ankle in a neutral position for 6 weeks (group 2). Patients were assessed at 3, 6, and 14 months and 11 years postoperatively. Results: There were 37 patients (74%) evaluated at a mean (±SD) of 11.0 ± 0.9 years. The mean Leppilahti score was 92.9 ± 5.6 in group 1 and 93.6 ± 7.2 in group 2 (P = .68). The mean isokinetic plantar flexion peak torque deficits or average work deficits in plantar flexion showed no differences between the groups with any angular velocity. Isokinetic strength changed minimally between 1 and 11 years compared with the unaffected ankle, but a mean deficit of 5% in peak torque and mean deficit of 8% in average work were still present after 11 years. On the contrary, isometric plantar flexion strength recovered significantly, with only a 2.4% difference at 11-year follow-up. Conclusion: After the 11-year follow-up, early mobilization and immobilization in tension after Achilles rupture repair resulted in similar clinical outcomes and isokinetic strengths. Regardless of patient satisfaction with the operative treatment, calf muscle strength did not recover normally even at 11-year follow-up.

A Retrospective Comparative Study With Historical Control to Determine the Effectiveness of Platelet-Rich Plasma as Part of Nonoperative Treatment of Acute Achilles Tendon Rupture

The aim of this study was to evaluate the effectiveness of platelet-rich plasma (PRP) in the nonoperative treatment of acute Achilles tendon rupture. This was a comparative study that included a prospective cohort and a historical control group. The control group was formed from a randomized trial in which one arm of the trial underwent nonoperative treatment, including accelerated functional rehabilitation after acute Achilles tendon rupture identical to that performed in the prospective treatment group. Patients in the prospective group were recruited consecutively and were administered 2 injections of PRP during the first 2 weeks after the injury. The primary outcome was isokinetic plantar flexion strength at 1 and 2 years after injury. Secondary outcomes included range of motion (ROM), calf circumference, and Leppilahti score. The ankle-hindfoot scale (American Orthopedic Functional Ankle Scale [AOFAS]) was administered to patients who received the PRP injection in the prospective group but was not measured for the historical group. A total of 73 patients participated in the prospective PRP study group and were compared with a retrospective control group of 72 patients from a previous randomized controlled trial (RCT). The mean difference between groups in isokinetic plantar flexion strength (injured/uninjured) at 1 year after injury was -4.3% (95% confidence interval [CI], -15.9 to 7.3; P = .5) and 2.4% (95% CI, -8.6 to 13.5; P = .7) at 30°/s and 60°/s, respectively. Results at 2 years after injury were -3.1% (95% CI, -13.5 to 7.2; P = .6) and 4.8% (95% CI, -3.5 to 13.1; P = .3) at 30°/s and 60°/s, respectively. All secondary outcomes were also not statistically different. The results of this study suggest that there is no measurable clinical benefit to the addition of PRP to the treatment regimen for nonoperatively treated acute Achilles tendon rupture. Level III, retrospective comparative study.

태권도, 축구, 체조 선수들의 균형능력과 근력, 근지구력의 상관분석

The purpose of this study was to investigate a relationship among Taekwondo, soccer and gymnastic athletes their balance abil- ity and lower extremity muscle strength, muscle endurance and also whether these variables show differences by sports type. For this purpose, 10 Taekwondo athletes, 10 soccer athletes and 10 gymnastic athletes that is a high school in I area were selected and their balance ability, isokinetic muscle strength and muscle endurance were measured by using force platform (AMTI) and isokinetic measurement (HUMAC NORM). Then the following results were obtained by conducting pearson product-moment cor- relation analysis and one-way ANOVA. In case of both right and left foot one-leg standing with open-eyes, there was a relation between both knee extension maximal muscle strength of Taekwondo, soccer, gymnastic athletes and balance ability, and in case of right foot one-leg standing with open-eyes, there was a relation between that is right plantar flexion and dorsi flexion maximum muscle strength and muscle endurance of Taekwondo, soccer, gymnastic athletes and their balance ability. Furthermore, in case of left dorsi flexion maximum muscle strength, there were significant differences in order of Taekwondo, gymnastics and soccer, and for isokinetic plantar flexion maximum muscle endurance, both right and left showed significant differences in order of Tae- kwondo, gymnastic and soccer.