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| ABT In Clinical Practice |
| Author: Dr. Naushin Aslamkhan-Chaudhry MB BS |
| Are We Really Balancing Total Knee Replacements? The Results Of A Trial, Objectively Assessing Soft Tissue Balance Intra-Operatively |
| Authors: Mr Peter Hull (T&O SpR), Mr Charlie Lewis (T&O SpR) Miss Helen Whalley (T&O SpR) Mr Andreas Sambatakakis (T&O Consultant) Solihull Hospital , Lode Lane, Solihull, B91 2JL |
| Chronic Achilles Tendinopathy: A Prospective Randomized Study Comparing the Therapeutic Effect of Eccentric Training, the AirHeel Brace, and a Combination of Both |
| Authors: Wolf Petersen,*† MD, Robert Welp,‡ MS, and Dieter Rosenbaum,‡ PhD From the †Department of Trauma, Hand, and Reconstructive Surgery and the ‡Movement Analysis Lab, Orthopaedic Department, University Hospital Muenster, Muenster, Germany |
| Cartilage Injuries in the Athlete |
| Author: Satish Kale |
|
ABT In Clinical Practice
Blood transfusion (also referred to as banked, allogenic or homologous transfusion) is a powerful accessory to the practice of modern medicine. At one time it was an unquestioned part of patient care however its use is now being re-evaluated because of growing concerns for safety and shortages and costs.1 Since the AIDS epidemic in the 1980’s, followed by Hepatitis C, interest in alternative sources to allogenic blood is growing.
Author: Dr. Naushin Aslamkhan-Chaudhry MB BS Autologous Blood Transfusion
Cell salvage, also known as autologous blood transfusion is designed to reduce the need for banked blood. It involves the collection of the patient’s own blood from the surgical sites which can then be transfused back into the same person after surgery as required. It is an endorsed blood conservation strategy which is now being practised in many elective surgical procedures.
The most recent stimulus for looking at alternatives to allogenic blood is the evidence that allogenic transfusions are associated with increased risk of myocardial infarction, heart failure, stroke, multiorgan failure and death.
Another important reason would be the growing demand of blood with a declining population of qualifying willing donors. The most recent concern is that vCJD could be transmitted by blood transfusion.2 This has resulted in a more stringent procedure of donor selection and removal from the donor pool of those who may have been exposed to vCJD. The possibility of prion screening for vCJD in the future would result in the elimination of a sizable population of donors from the volunteer donor pool, which would result in blood becoming even scarcer.
The blood supplies in the UK are considered one of the safest in the world however efficient screening of blood has resulted in mounting costs with a unit of blood now costing around £150. In the future the costs are expected to escalate even more:
Despite all the care, safety issues still persist, according to “Serious hazard of blood transfusion” report 2007. “Incompatible blood components transfused” remains the leading event reported with over 400 cases.3
 The first transfusion is started within 6 hours of collection and the second bag can be used to collect blood for a further 6 hours, as indicated in the AABB guidelines.8
The other added benefit of the CellTrans™ is the Pall LipiguardR filter which reduces the fat globules, microaggregates, activated leucocytes as well as complement before reinfusion. The Pall LipiguardR filter is supplied as part of the CellTrans™ device.
In an audit from North Middlesex hospital, approximately 30 units of red cells were saved over the 22 patients who received the CellTran™ system allowing the use of this precious and scarce resource on other patients. This identified a significant saving of £2400 based on the cost of one unit of blood being £120.
Another audit done at Nuffield hospital, St Mary’s Bristol compared CellTrans™ versus conventional low vacuum drains in patients undergoing primary hip arthroplasty. The use of CellTran™ allowed the rate of donor transfusion to reduce from 40% to 6%.7 Other data has shown that length of stay in the hospital was significantly reduced compared with the suction drain group.9
If postoperative ABT is routinely used in clinical practice for knee arthroplasty as recommended by the British Orthopaedic Association, it would generate a multi million pound saving to the NHS. If this use is extended to patients undergoing primary hip arthroplasty, and the use of allogenic transfusion brought down from its present 40% to about 10%, this would achieve an additional saving of an equivalent amount.7 In addition to cost saving it would meet the objective of using allogenic blood more appropriately and saving this resource for patients in whom ABT cannot be used.
The BBT guidelines stress the need for providing training and information to the clinicians undertaking transfusion. The guidelines also stress the importance of the provision of timely written information about blood transfusion and its alternatives to patients at risk of needing a blood transfusion.1
The Department of Health has focused attention on blood transfusions because of increasing demand for blood together with the donor shortage. It seems appropriate that whenever possible hospitals should use Post operative cell salvage devices which offer a benefit to the patient and save this scarce resource for other patients
Summit Medical Ltd Tel: +44 (0)1541 821311 Email: info@summit-medical.co.uk Web: www.summit-medical.co.uk Are We Really Balancing Total Knee Replacements?
The Results Of A Trial, Objectively Assessing Soft Tissue Balance Intra-Operatively Authors: Mr Peter Hull (T&O SpR), Mr Charlie Lewis (T&O SpR) Miss Helen Whalley (T&O SpR) Mr Andreas Sambatakakis (T&O Consultant) Solihull Hospital , Lode Lane, Solihull, B91 2JL Abstract
Purpose: To determine whether subjective methods of assessing gaps and balance during total knee replacements are accurate.
Scope: 9 knees were included. Once the surgeon had balanced the knee using his standard subjective methods, an objective measure of the gaps and balance was taken using the Stryker knee balancer.
33% of knees were found to have unequal flexion extension gaps.66% of knees were found to have imbalanced soft tissues. Introduction
Classical knee arthroplasty teaching states that when performing total knee replacements (TKRs) equal flexion, extension gaps should be achieved and equal soft tissue tension should be attained.1
In 1985, Insall stated that correct soft tissue balancing was the most important factor in determining the long term outcome following TKRs.1 Previous work, by the senior author has demonstrated the detrimental effect of imbalanced knee replacements.2
Various subjective measures are utilised by surgeons to assess flexion extension gaps and soft tissue tension, including the use of spacer blocks, finger tension technique, and the ‘feel’ of soft tissue tension on the medial and lateral sides.
There also objective measures of soft tissue balance and flexion extension gaps available, one commercially available product is the Stryker knee balancer.
Method
Two specialist registrars; both of whom were experienced in the use of the balancer with the senior author, performed 9 TKRs, under the supervision of other experienced consultant knee surgeons, all of whom used subjective measure of gaps and soft tissue balance. When the surgeon was ready to implant the definitive component, an objective measure of the flexion extension gaps, and soft tissue tension was made using the Stryker Knee balancer.
Results
The results for all 9 patients are shown in table 1. All TKRs were relatively ‘simple’, as they all had a pre-op varus deformity of 5-15 degrees and were being performed for primary osteoarthritis.
These results show that 3 of the 9 (33%) knees balanced subjectively had unequal flexion-extension gaps, and 6 of 9 (66%) had unequal soft tissue balance. Two of the knees ended up being imbalanced into valgus, due to the initial soft tissue release being too great.
Discussion
In the 1970’s Insall 3 and Freeman 4 were the first to emphasize the concept of soft tissue balancing and introduced the use of a spacer-tensor device in order to assess the symmetry of the flexion and extension gaps. They expressed the view that correct soft tissue balancing would increase the longevity and decrease revision rates in Total Knee Arthroplasty.
Sambatakakis et al,2 described the “cement wedge sign”: a smoothly tapering wedge of cement visible beneath the horizontal portion of the tibial component on anteroposterior radiographs. Evidence suggested this indicated persistent soft tissue imbalance after Total Knee Arthroplasty and was associated with a highly significant increase in radiolucent lines at the tibial bone-cement interface at follow-up.
Instability post-operatively is often caused by incorrect ligament balancing.5 The relationship between the adequacy of ligament releases and the severity of polyethylene wear, as found at revision surgery, was confirmed by Wasielewski et al.6 The soft tissue imbalance was associated with component loosening, polyethylene wear and overall failure of the Total Knee Arthroplasty.
In 1996, Attfield et al7 reported that knees balanced in both full extension and in flexion showed a significant improvement in proprioception post-operatively, whereas those balanced in extension only, did not.
Unitt et al8 have shown that, extensive soft tissue releases to obtain accurate objective balance significantly improve short-term clinical outcome without increasing complications and that balancing an imbalanced knee significantly improves short-term knee outcome.
Our results have shown that even in relatively ‘simple’ TKRs, subjective methods of assessing gaps and balance are inaccurate. They have also demonstrated that performing medial releases without an objective guide, can lead to the knee being imbalanced into valgus, due to too great an initial release.
A number of criticisms of the study do exist. Although both SpRs taking the measurements with the balancer were experienced in its use with the senior author, there is no torque meter on the balancer. Therefore 100% reliable measurements cannot be guaranteed, as it is possible different torques were produced in the measurement of the gaps. This flaw in the design of the balancer as a research tool is currently being worked on with the manufactuers.
A potential flaw in the surgical technique, using either subjective or objective techniques of balancing is
References
Chronic Achilles Tendinopathy: A Prospective Randomized Study Comparing the Therapeutic Effect of Eccentric Training, the AirHeel Brace, and a Combination of Both
Chronic Achilles tendon pain, manifested as a localized painful thickening of the tendon, is relatively common among middle-aged recreational athletes.1-3,5,9,11,15,21 Gradual onset of pain in the Achilles tendon with structural changes in the midportion of the tendon (2-8 cm above the calcaneal insertion) is called tendinopathy and is generally considered to be a difficult condition to treat.2,10,11,22,24,28
Several studies have demonstrated that treatment by heavy-load eccentric calf muscle training leads to good clinical results, with decreased pain and full recovery to previous activity level.2,7,8,17,18,23,28-30 Therefore, this treatment strategy has to be considered the standard for the treatment of chronic tendinopathy of the Achilles tendon. However, our clinical experience with eccentric training has shown that some patients discontinue this treatment because of the experience of pain during exercise.
Conservative treatment options other than eccentric training for chronic Achilles tendon pain have previously been less encouraging.4 In one literature review, the authors stated that many common treatments such as rest, strength and flexibility exercises, anti-inflammatory agents, or corticosteroids do not alter the natural course of this disease.4 These inconclusive results are explained with the multifactorial origin of Achilles tendinopathy so that one single treatment appears insufficient. Very few prospective randomized controlled trials exist to assist in choosing the best evidence-based treatment.4
Chronic Achilles tendinopathy is often associated with paratendinitis.13,19,21,24 Local massage is regarded as an important technique to loosen adhesions in paratendinopathy and to remove metabolites and other waste products via the venous plexus of the paratenon, and might have a positive effect on the course of chronic Achilles tendinopathy.16
The AirHeel brace (Aircast, Vista, Calif) is specifically designed to treat Achilles tendinopathy. The manufacturer claims that the 2 interconnected air cells located under the heel and above the calcaneus apply pulsating compression with every step to help reduce swelling and discomfort, and enhance circulation by a local massage effect, but these effects have not been proven with scientific studies.
The purpose of this prospective randomized study was to evaluate 3 different treatment protocols for chronic midportion tendinopathy of the Achilles tendon: (1) eccentric training, (2) the AirHeel brace, and (3) a combination of eccentric training and the AirHeel brace.
Our first hypothesis was that the AirHeel brace improves symptoms of chronic noninsertional tendinopathy. The second hypothesis was that the combination of eccentric training with the AirHeel brace has a synergistic effect.
Authors: Wolf Petersen,*† MD, Robert Welp,‡ MS, and Dieter Rosenbaum,‡ PhD From the †Department of Trauma, Hand, and Reconstructive Surgery and the ‡Movement Analysis Lab, Orthopaedic Department, University Hospital Muenster, Muenster, Germany
Material And Methods
One hundred patients were included in the study and randomly assigned to one of the 3 different treatment groups (Table 1): group 1, eccentric training (37 patients); group 2, AirHeel brace (35 patients); and group 3, combination of the AirHeel brace and eccentric training (28 patients).
The patients were recruited by announcing the study in local newspapers. Randomization for assigning the subjects to a treatment group was achieved with selecting random numbers between 1 and 3 in Microsoft Excel (Microsoft Corp, Redmond,Wash).
All of these patients had been suffering from a gradually evolving painful condition in the Achilles tendon located at the midportion for at least 3 months. Most of the patients were recreational athletes involved in activities such as jogging or running (29%), walking (15%), or other sports activities (33%).
In all cases, the diagnosis was based on clinical examination performed by the same investigator (R.W.), showing a painful thickening of the Achilles tendon located at a level of 2 to 6 cm above the tendon insertion. In all tendons, the diagnosis was confirmed by ultrasonography, in which the tendon changes were described as a local thickening of the tendon, irregular tendon structure with hypoechoic areas, and irregular fiber orientation.
In all cases, the condition caused pain during tendon loading that limited the desired activity level. Most patients (87 of 100) had previously been advised to treat the problem by resting the affected leg. A majority of the symptomatic tendons had been treated with other treatment regimens (nonsteroidal anti-inflammatory drugs, 78; local cortisone injection, 3; physiotherapy, 45; or orthotic treatment, 23) without satisfactory effect on the Achilles tendon pain. Patients with previous surgery or tendon rupture were excluded from this study.
At the initial visit, a clinical examination with assessment of height, body weight, and assessment of local tenderness was performed in every patient. The amount of pain during rest and activity was evaluated by the patients on a 10-cm-long visual analog scale (VAS). On the VAS, the amount of pain is recorded from 0 to 10 cm, where no pain is recorded as 0 and severe pain is recorded as 10. The joggers registered the amount of pain during jogging, runners during running, and walkers during walking (ie, registration depended on the patient’s type of activity). Function of the hindfoot region was assessed with the American Orthopaedic Foot and Ankle Society (AOFAS) hindfoot scale.14 Every patient completed the Short Form-36 (SF-36). Ultrasound examination was performed to evaluate thickening of the tendon in its midportion (2-6 cm above the insertion) and the presence of paratendinitis. The tendon diameter was evaluated on longitudinal cross-sections. Other findings such as hypoechogenic structures, nodules, etc were also noted. All patients with pain at the insertion of the tendon (insertional tendinitis) or Haglund deformity were excluded from the study.
Eccentric Training Model
All patients in this intervention group were instructed on how to perform the eccentric training by the same investigator (R.W.). They were given practice instruction and a written manual on how to progress. The correct execution of the exercises was confirmed after 6 weeks. The training protocol was adopted from previous studies.2 The patients were instructed to perform the eccentric exercises 3 times daily, 7 days per week, for 12 weeks. They were also advised to use stable shoes when performing the exercises.
In the beginning, the loading consisted of the body weight. From an upright body position and standing with the whole body weight on the forefoot, with the ankle joint in plantar flexion (Figure 1A), the calf muscles were loaded by lowering the heel (Figure 1B). Two types of exercises were used. The calf muscle was eccentrically loaded both with the knee straight (Figure 1C) and, to maximize the activation of the soleus muscle, with the knee slightly bent. The calf muscles were only loaded eccentrically; no following concentric contraction was performed, as the patients were instructed to use the noninjured leg and/or the arms to return to the starting position.
AirHeel Treatment
The AirHeel is a specifically designed brace for the treatment of Achilles tendinopathy (Figure 2). Patients were instructed to wear the AirHeel during the daytime.
Evaluation
The evaluation of the efficacy of the treatment regimen was performed after 6 and 12 weeks of the intervention. At each follow-up, the outcome was assessed with the VAS for pain at rest, during gait, and during sports activities; the AOFAS hindfoot scale; the SF-36; and ultrasound examination. To avoid bias, the evaluation of the VAS and the SF-36 was done by the patient alone. All patients were questioned for possible adverse effects of the treatments (eg, tendon rupture, discomfort, severe pain).
For a 1-year follow-up, patients were asked to fill out the questionnaires for the AOFAS, report the pain on the VAS, and to report whether they reached their preinjury sports level.
Ethics
The experimental protocol for this study was approved by the Ethical Committee of our University. All patients gave their consent to participate in this treatment model.
Statistical Evaluation
Commercial software (StatView 5.0, SAS Institute, Cary, NC) was used for all statistical calculations. A repeated-measures analysis (3 groups by 4 measurements) was performed. The results are expressed as mean ± standard deviation (SD) throughout this article. A P value < .05 was considered significant.
Results
Anthropometric Data of the 3 Treatment GroupsThe anthropometric data of the patients involved in the present study show that there were no significant differences in age, duration of symptoms, gender, height, weight, and body mass index between the 3 treatment groups (Table 1). The total dropout rate during the 12-week treatment period was 14% and did not differ between the 3 treatment groups. Some of the dropout patients discontinued the eccentric training because of severe pain experienced during the exercises. The main reason for dropout in the AirHeel group was discomfort due to poor fitting of the brace. At the 1-year follow-up, two patients (1 in the AirHeel group, 1 in the eccentric training group) had undergone surgery. Twelve patients were lost to follow-up. Figure 3 shows the fate of all patients entering the study.
The AOFAS score improved significantly during the course of the study, from 77 points to 85 points after 6 weeks, to 89 points after 12 weeks, and to 85 points after 54 weeks of treatment (Figure 4) without any significant differences between the 3 different treatment groups. At the 1-year follow-up, the AOFAS score was still improved by 10% in the eccentric training group and in the brace group, and by 12% in the combination group as compared with the pretreatment situation. These differences were significant (P < .0001). Pain
Pain during activities of daily living assessed with a VAS (where 0 cm = no pain and 10 cm = severe pain) improved significantly in all 3 treatment groups (Figure 5). In group 1 (eccentric training) and group 3 (combination), pain was reduced 20% and 22% after 6 weeks and 60% and 56% after 12 weeks, respectively. In group 2 (AirHeel), pain was reduced by 41% after 6 weeks with no further decrease after 12 weeks (35%). At the 1-year follow-up, pain was still reduced by 30% in the eccentric training group, by 27% in the brace group, and by 53% in the combination group as compared with the pretreatment situation. These differences were significant (P < .0001).
Pain during walking was higher than pain during activities of daily living, but there was also a significant improvement of pain during walking assessed with the VAS in all 3 study groups (Figure 6). In group 1, there was a 25% decrease of pain after 6 weeks and 71% decrease after 12 weeks. In group 2 and in group 3, there was a pain reduction of 43% and 36%, respectively, after 6 weeks but there was no significant further pain reduction after 12 weeks (group 2, 50%; group 3, 56%). At the 1-year follow-up, pain during walking was still reduced by 45% in the eccentric training group, by 46% in the brace group, and by 64% in the combination group as compared with the pretreatment situation. These differences were significant (P < .0001).
The highest pain level (overall 5.7) was experienced during sports activities. In each treatment group, the pain level decreased significantly at 6 and 12 weeks (Figure 7). At each time point, there was no significant difference between the 3 treatment groups. At the 1-year follow-up, pain was still reduced by 51% in the eccentric training group, by 47% in the brace group, and by 74% in the combination group as compared with the pretreatment situation. These differences were significant (P < .0001).
In all pain categories, the eccentric training group and the brace group had lost some of the benefit seen after the 12-week treatment period whereas the combination group showed a further improvement. However, no significant group differences were seen in any of these parameters.
Ultrasonography
At the initial examination, the sagittal tendon diameter was significantly greater than the diameter of the healthy contralateral side. However, during the course of the study, there was no change in the tendon diameter in any of the 3 treatment groups.
Short Form-36
The SF-36 was used for quality of life assessment at time point 0, and after 6 and 12 weeks of treatment (Table 2). Only 2 of the 8 different categories improved significantly during the course of the study—function and pain. Function improved by about 13% in group 1 and in group 2. In group 3, function improved by about 17%. Pain also improved significantly, by about 13% in group 1 and group 2. In group 3, pain improved by 19%. There was no significant difference between the 3 treatment groups.
Return to Sports
Return to preinjury sports level was evaluated after 54 weeks. Ninety percent of patients reached their preinjury activity level. There was no statistical significant difference between the groups.
Discussion
Although the amount of improvement was very modest, the results of this study support our first hypothesis. A 12-week treatment with the AirHeel brace improved symptoms of patients with chronic midportion tendinopathy of the Achilles tendon. The second hypothesis of this study was only partially supported by the results of the present study. Only the SF-36 showed a synergistic effect of both treatments. Function improved by about 13% in the eccentric training group and in the AirHeel brace group. Function improved by about 17% when both treatments were combined. Pain also improved significantly, by about 13% in the eccentric training group and in the AirHeel brace group. Pain improved by about 19% in the combination group.
It is difficult to compare outcome between studies because different measures of outcome are often used.4 Although patients’ perception of general health is considered to be increasingly important, only a few studies on Achilles tendinopathy have used this as a measure of outcome.6,20 The SF-36 is one of the most widely used instruments for addressing patient self-assessment.32 Clinical experience of patients with intra-articular calcaneus fractures has shown that limitations in many fields of daily life are to be expected. In a study about the outcome after surgical treatment of calcaneal fractures, Westphal et al33 showed that the SF-36 detects more limitations in general health status than other classic instruments. In this context, the SF-36 seems to be an ideal tool for measuring outcome and should be used in future studies. In our study, only 2 of the 9 SF-36 item scores improved significantly - pain and functional status. The amount of improvement in these 2 categories was quite low. It is difficult to judge if this moderate increase represents a “practical” improvement from the patient’s point of view.
The SF-36 is not a disease-specific instrument; therefore, it is not capable of detecting specific symptoms and limitations in patients with Achilles tendinitis. Another widely used instrument for the assessment of hindfoot disorders is the AOFAS score.14 With this score, the eccentric training group and the AirHeel group improved but there was no synergistic effect when both treatments were combined. The same result was obtained with the VAS assessment of pain.
Although we could not replicate the very good results after eccentric training found in other studies, the results of this study support findings of previous studies regarding the effect of the eccentric training.2,7,8,18,28-30 Several previous studies could demonstrate that eccentric exercises improve pain and function in cases of chronic midportion tendinopathy of the Achilles tendon. The concept of eccentric training as treatment for chronic Achilles tendinopathy was introduced by Stanish et al.30 The exact background of the good clinical results achieved with this method has long been unknown. It was believed that eccentric loading of the tendon enhances collagen fibril alignment with increased tensile strength, encourages fibroblast activity, and prevents adhesions between the healing tendon and adjacent tissue.7
Recent studies have shown that an effect on neovascularization could be responsible for the good result with eccentric training in chronic midportion Achilles tendinopathy.8,22 In a clinical study, Öhberg et al23 showed that in the majority of tendons with a good result after eccentric training, the neovessels that had been demonstrated in all tendons before treatment had disappeared at follow-up. In the 5 tendons with a poor result of treatment, there was remaining neovascularization.23 Several studies have shown that tendons with chronic tendinopathy had significantly more blood vessels than normal tendons.23,25-27 The occurrence of neovascularization in the area with tendon changes, demonstrated with color Doppler examination simultaneously with ultrasonography, has been shown to possibly be correlated with pain in chronic midportion Achilles tendinopathy.23 From another study on biopsies from Achilles tendinopathy tissue, we know that there are nerve structures in the proximity of the vascular wall1; consequently, the area with neovascularization should be considered as an area with neovessels and accompanying nerves. Alfredson et al3 used microdialysis and could show that concentrations of the neurotransmitter glutamate were significantly higher in tendons with chronic painful tendinopathy compared with pain-free (normal) Achilles tendons. In recent years, the importance of glutamate as a mediator of pain in the central nervous system has been emphasized.
In contrast to eccentric exercises, the explanation for the effect of the AirHeel brace demonstrated in this study is largely unknown. We speculate that the cyclic massage effect of this brace supports transport of metabolites such as glutamate or lactate via the venous plexus of the inflamed paratenon. A second explanation could be that the brace loosens adhesions built between the tendon, paratenon, and the surrounding tissue. Further experimental studies are needed to evaluate the cause of the positive effect of the AirHeel brace on chronic Achilles tendinopathy as documented in this prospective randomized controlled trial. To our knowledge, there are no clinical studies about the AirHeel brace for chronic Achilles tendinopathy in the literature. Kavros et al12 evaluated the efficacy of the AirHeel brace in the treatment of plantar fasciitis. In this study, the AirHeel group demonstrated significant improvement in pain.12
Poor methodology is one suggested reason for the weak evidence for treatment of tendinopathy.4 Therefore, care was taken that the methodologic suggestions proposed by Tallon et al31 were met in the present study. The complete study design was approved by the Ethical Committee of the medical faculty of our University as a prospective randomized controlled trial. Because placebo treatment was regarded as unethical,we chose the well-established eccentric training as a control group. A power analysis revealed that a minimum of 30 patients were needed in each group to detect a medium effect of the treatment modality. The treatment period was documented in detail for every patient to control for treatment adherence and compliance. The outcome assessments (AOFAS score, SF-36, VAS for pain) were in a written form with minimal investigator assistance. Because the literature provides no outcome instruments that have been validated for Achilles tendinopathy, we decided to use as many different outcome instruments as possible. All outcome instruments were used in previous studies about Achilles tendon or hindfoot disorders. Ultrasonography was performed to confirm the diagnosis of midportion tendinopathy and to diagnose associated paratenonitis. However, thickening of the tendon and structural changes were not inclusion criteria. All patients with pain from the insertion of the tendon were excluded from the study because previous studies have shown that pain at this location has a different origin (Haglund deformity, insertional tendinopathy) and does not respond well to eccentric exercises.2
Gray scale ultrasonography is commonly used to investigate Achilles tendon injuries and has been shown to be a reliable and cost-effective method of identifying abnormalities such as increased tendon thickness, hypoechoic areas, and irregular structure. Therefore, we decided to use ultrasonography to study tendon thickness and tendon structure before and after treatment with eccentric training. None of the treatment strategies tested in the present study could influence these structural changes. The short follow-up period for the ultrasound examination might be an explanation for this finding. Fahlström et al8 could show that tendon width had decreased significantly 3.8 years after eccentric calf muscle training. Furthermore, before treatment all patients had hypoechoic areas and an irregular tendon structure, but at follow-up the tendon structure was normal (no hypoechoic areas and regular structure) in 19 of the 26 tendons. Fahlström et al8 speculated that the eccentric training regimen might induce a response that normalizes the concentrations of glycosaminoglycans and possibly enables normalization of the fiber arrangement, resulting in decreased tendon thickness. In this study, in most patients the pain in the tendon diminished and then disappeared during the 12-week treatment period. It is conceivable that the pain recedes during the early part of a possible remodeling phase, but normalization of tendon thickness and structure may be more timeconsuming.
When no differences in effect can be found between treatment groups, one should always consider a type II error. However, a power analysis has shown that a minimum of 30 patients was needed to detect differences between eccentric training and no treatment. Another limitation is that from the present study, one cannot exclude the effects of placebo, similar in all 3 groups. However, a placebo group was not approved by our local ethics committee. Theoretically, there could be a risk for contamination between groups in randomized study. However, all patients of the heel brace group were instructed not to perform any kind of strengthening exercises on their own. The limitations of the methods used in the present study inhibits our ability to draw any definite conclusions. This study could not demonstrate any significant differences between treatment with the AirHeel brace and an eccentric training program in patients with chronic Achilles tendon pain. No synergistic effects could be found when both treatment strategies were combined.
Further research is needed to evaluate whether the AirHeel brace is an alternative treatment option for patients with chronic Achilles tendinopathy.
Acknowledgment
The AirHeel brace was provided by Aircast Europe, Neubeuern, Germany.
References
Cartilage Injuries in the Athlete
Author: Satish Kale Introduction
With a global increasing in sporting activity there is a corresponding increasing in the incidence of joint trauma and consequently cartilage injuries. As patients get more demanding and want to return as quickly as possible to their pre-injury activity levels, it is imperative that techniques are discovered and developed to treat these injuries in an emergent way. Much progress has been made but the ultimate dream of cartilage self-induced regeneration has remained largely utopian.
Articular or hyaline cartilage is an extremely smooth, hard material, made up of the protein collagen, which lies on a bone’s articulating surfaces. Its function is to allow for the smooth interaction between two bones in a joint and in spite of being only a few millimeters thick has an amazing resilience to compressive forces. Thus, if injured it can lead to impairment in the fluidity of joint movement. In addition articular cartilage is extravascular, meaning that it has no direct blood supply. This means that once injured it is extremely slow to heal.
Histology of Articular Cartilage
The mechanical and structural capacity of the articular cartilage is dependent on the integrity of its extracellular matrix. Chondrocytes sparsely distributed throughout a matrix of structural macromolecules work together with a hydrated extracellular glycosaminoglycans to attract and then sequentially extrude water. Water constitutes between 65-80% of the entire wet weight of articular cartilage and is about 15% more concentrated at the surface than in the deeper zones. Extracellular components of collagen, proteoglycans, non-collagenous proteins and water combine to provide the shear, compressive, and permeability characteristics of cartilage. It is the composition and highly complicated interaction of these components that makes regeneration and replacement techniques challenging.
Functions of the Articular cartilage
The functions of articular cartilage include load transmission and distribution, smooth articulation, and aid in lubrication. Load transmission and distribution is due to the ability of the structural matrix to deform, which leads to increased joint contact areas and distributed mechanical stresses. It also has the ability to respond to applied loads through fluid exudation and redistribution within the interstitial tissue. Some texts also mention about a proprioceptive function, which aids in recognizing and limiting joint-deforming forces and induce protection.
What is the Cartilage Crisis?
Most of the joints in the body are synovial joints, that is movable, lubricated joints which are able to provide normal pain-free movement because of the unique properties of the articular cartilage. The articular cartilage covers and protects the ends of the bones in joints. The knee is the largest synovial joint.
At the top of the knee are the massive quadriceps muscles, which cause the knee to extend. The hamstring muscles are at the back of the knee and cause it to flex. The knee joint has a synovial membrane, which is tissue that lines the noncontact surfaces within the joint capsule. The ends of the tibia, femur, and the patella are covered by articular cartilage. This is the structure that described to be in crisis.
Causes of Cartilage Damage
The common causes of cartilage damage are:
Diagnosis and Investigations
ArthroscopyThe articular cartilages are divided into 5 compartments including lateral and medial tibial, lateral and medial femoral and patellar compartments. The articular cartilages are graded using a modified Outerbridge classification. Grade 0 indicated intact cartilage, grade 1 chondral softening with normal contour, grade 2 superficial fraying, grade 3 surface irregularity and thinning and grade 4 full thickness cartilage loss. The grades of articular cartilage were compared with cartilage volume measurements. MRI MRI, by virtue of its superior soft-tissue contrast, lack of ionizing radiation and multiplanar capabilities, is superior to more conventional techniques for the evaluation of articular cartilage unlike radiography, MRI provides: A. Provide direct visualization of the hyaline cartilage (as well as the meniscus and bone) B. Accurate quantification with sensitivity to change C. MRI is also less subject to positional change, which is a particular problem in the interpretation of small changes in radiological measures in longitudinal studies Articular cartilage lesions may be categorized as degenerative or traumatic in cause. Early degenerative disease may be seen on MRI as fibrillation or surface irregularity, cartilage thinning or thickening or intrachondral alterations in signal intensity. Advanced degenerative chondral lesions manifest on MRI as multiple areas of cartilage thinning of varying depth and size, usually seen on opposing surfaces of an articulation. Other associated MRI findings of degenerative cartilage disease include central and marginal articular osteophytes, joint effusion, and synovitis. In contrast, traumatic chondral lesions generally manifest on routine clinical MRI as solitary focal cartilage defects with acutely angled margins. Traumatic chondral injuries are typically the result of shearing, rotational, or tangential impaction forces and often result in high-grade partial- or full-thickness cartilage tears or in osteochondral injuries of cartilage and the underlying subchondral bone. As a rule, recognition of a traumatic chondral defect should prompt careful inspection of the joint for a displaced intraarticular chondral body. Cartilage Mapping Using specialized image processing algorithms, individual structures, such as the articular cartilage, can be isolated from a MR image and quantified in a variety of ways, including total volume measurement and thickness mapping. The precision error for measuring cartilage volume is approximately 2 %, while that for cartilage thickness mapping is 0.3 mm. Pressure Point Maps Newer MRI machines and specialized sequences allow application of stress to the knee while the patient is in an MRI scanner. It has the ability to simulate squatting and stresses with the patient lying down. The result is a detailed picture of how the ligaments move and how the surfaces of the joint slide over each other during movement. Pressure points that appear and disappear transiently as the knee moves can be mapped and measured. Such points are potential sources of injury to the cartilage. This allows us to do quantitative measurements to evaluate how the repair and recovery are progressing. A more advanced MRI technique called MRI spectroscopy provides an even more accurate description of the health of tissues in the knee. While standard MRI essentially gives a picture of tissue density and water content, MRI spectroscopy offers a detailed picture of lipids, saturated and unsaturated fats, metabolic products and many other cellular markers. New Techniques for the Objective Evaluation of Repair Tissue
Dr. J-K Suh and co-workers from the University of Pittsburgh are developing an ultrasonic indentation probe, which can be used arthroscopically to measure articular cartilage thickness and mechanical properties. Dr. Suh presented data supporting the accuracy and reproducibility of the technique. Dr. S. Treppo from MIT has described an electromechanical spectroscope probe that can detect cartilage degradation and may facilitate the evaluation of intrinsic material properties.
Scoring Cartilage Injuries
At the Symposium of the International Cartilage Repair Society (ICRS) in 1997, a working group presented The Cartilage Standard Evaluation Form, adapted from the International Knee Documentation Committee system. Patient data such as cause of injury, age at the occurrence of injury, onset of symptoms, sporting activities, knee pain, subjective knee function (percentage of function compared to the normal knee), previous surgery, and activity level were included. According to this system, the depth of cartilage defects is ranked on a 4-grade scale. The size and the anatomical localization further describe the defects. The defects are also outlined by the surgeon on standard grid maps including frontal and lateral views of the articular surfaces of the knee.
ICRS Grade I is superficial fissuring of the articular cartilage. Grade II is fissuring extending to less then half the normal cartilage depth. Grade III is fibrillations in the articular cartilage greater than half the normal cartilage depth and up to but not through the subchondral plate. Grade IV is significant lesions penetrating the subchondral bone.
Treatment
Treatment of articular cartilage defects in the knee has been attempted in numerous studies and all with varying levels of success. Treatment can be directed at either treating the symptoms or trying to affect articular repair or regeneration Repair refers to the restoration of a damaged chondral surface with new tissue that resembles but does not duplicate the structure, biochemical makeup, function and durability of articular cartilage. Regeneration denotes the formation of new tissue indistinguishable from normal articular cartilage. There is also the component of other associated pathology in conjunction with focal articular cartilage damage. A few of the more common treatment methods are noted below.
Lavage: Lavage rids the knee of loose articular debris and inflammatory mediators that are known to be formed by damaged synovial joints. When arthroscopic lavage was performed in conjunction with mechanical debridement, there were improved results with about 88% short-term improvement. The results vary widely.
Bone marrow stimulation techniques: These procedures are theorized to stimulate and mobilize the mesenchymal stem cells to differentiate into cartilaginous repair tissue. Once disruption of the vascularized cancellous bone has occurred, a fibrin clot is formed and pluripotent cells are introduced into the area. These cells eventually differentiate into chondrocyte-like cells that secrete type I, II and other collagen types as well as cartilage specific proteoglycans after receiving mechanical and biological cues. The cells produce a fibroblastic repair tissue that on appearance and initial biopsy can have a hyaline-like quality. Unfortunately, over time the histological characteristics change into more predominantly fibrocartilaginous tissue.
Abrasion arthroplasty consists of debriding the articular defect to a normal tissue edge so that fresh collagen can be produced in the fibrin clot. The surface of the subchondral bone is exposed and penetrated to a depth of about 1 mm. Various reports show 12-53% reduced pain post-operatively. One of the potential problems with abrasion arthroplasty is the cell death produced by the heat of the abrasion burr and thus the destruction of the normal subchondral anatomy may impede any future repair or regeneration efforts.
Subchondral drilling consists of drilling through the defect to penetrate the subchondral bone. The technique was first popularized in the late 1950’s by Pridie and subsequent findings suggest the repair tissue introduced into the area can look like grossly like hyaline cartilage but histologically resembles fibrocartilage. Drilling also increases the possibility of cell death through heat necrosis.
Microfracture is another such technique in which the lesion is exposed, debrided, and a series of small fractures about 3 to 4 mm in depth are produced with a sharp instrument. Adjacent cartilage is debrided to a stable cartilaginous rim, and any loose fragments and fibrous tissue are removed. In microfracturing, there is no heat necrosis and the structural integrity of the subchondral bone is maintained. Fibrocartilage is produced and the clinical results remain mixed.
Soft tissue and osteochondral grafts: Utilizing either autologous tissue or allografts, these procedures are designed to provide a suitable environment for stimulation of the mesenchymal cells to produce type II collagen fibers. The success of such approaches is at least in part related to the severity of the abnormalities, the graft quality and technique utilized, age of the patient and correction of associated pathology. Attempts to provide the damaged articular cartilage with a viable durable surface has led to the introduction of soft-tissue grafts consisting of periosteum, perichondrium, fascia, joint capsule and tendinous structures into the defect. A critical component for success with these techniques is that the cambium layer must be placed facing into the joint and the surface must be secured adequately to avoid being knocked loose with joint motion. The potential benefits include the introduction of a new cell population along with an organic matrix, a decrease in the possibility of degeneration of the tissue before a new articular surface can be produced, and an increased protection of the graft from damage due to excessive loading.
Mosaicplasty: This technique consists of harvesting a bone-cartilage graft harvested from the posterior aspect of the femoral condyle and transplanted into the defect. The technique is also referred to as “mosaic-plasty” because of the mosaic fashion in which the grafts are implanted into the defect. Several authors have reported good to excellent results with 70-92% reduction of symptoms and improvement of function in short term observations. This technique has also been shown to restore subchondral bone, improve joint incongruity and actually restore an articular surface.
Osteochondral allograft: The small number of available graft sites and donor site morbidity could be avoided by the use of fresh or cryopreserved allografts. However, there are additional problems of allograft rejection, disease transmission, mismatch in sizes and congruity, and sparse supply. Those suffering from primary degenerative arthrosis or those with patella defects do not seem to benefit. Some investigators have found a 63-77% good result from 2-10 years.
Autologous chondrocyte cell transplantation (Auologous Cartilage Implantation ) or ACI: The limited ability of chondrocyte cells to effectively differentiate, proliferate, and regenerate hyaline cartilage has increased the interest in of transplanting live cells into chondral defects. This technique requires that no penetration of the subchondral bone occur in order to prevent the introduction of blood and the circulating fibrocytes. Short term follow-up reveals newly formed cartilage-like tissue covering about 70% of the transplanted area in animals. However, the results deteriorate significantly by one year. Two years after transplantation, about 66 % have good to excellent results with histological examination showing appearance of hyaline-like cartilage. Subsequent research has shown encouraging results regarding the use and efficacy of this technique for focal chondral defects but not for osteoarthritic joints. It is thought that the degradative enzymatic synovial fluid of the arthritic knee is not conducive to cell transfer by this technique.
Steps in ACI
Carbon Fiber Matrix Implant
Dr. G. Bentley reported 8 year follow-up of carbon fiber matrix implants, noting satisfactory results in 77% of patients overall, with 93% satisfactory results in the treatment of medial femoral condyle lesions.
Unconventional Therapies
Role of Prolotherapy in Cartilage Growth
Prolotherapy involves the injection of substances, such as hypertonic dextrose various minerals, Sarapin (extract of the pitcher plant), and various other substances including growth hormone which act by stimulating the structures to repair. The current theory of cartilage regeneration is that this irritation acts in the same mechanism as above in inducing the chondrocytes into the chondroblastic stage of development capable of proliferation and repair. It is impossible to do a double-blind study on Prolotherapy because even an injection of sterile water under the skin has a beneficial therapeutic effect. The jury is still out on the efficacy and the possible safety of these procedures.
Rehabilitation after surgery:
The objectives of rehabilitation are:
Cartilage Repair Registry
The Cartilage Repair Registry is an international, multi-center, prospective, outcomes assessment database. It is a program that longitudinally assesses clinical outcomes in cartilage repair patients. The Registry uses standardized data collection forms to track treatment outcomes in specific cohorts of patients undergoing implantation with autologous cartilage or CARTICEL and who have consented to participate in the registry. The Registry includes data on grade, location, and size of defects, concomitant procedures, previous surgeries and the Modified Cincinnati Knee Rating Score. The Registry hopes to provide valuable data to help address clinicians concerns regarding appropriate treatments and prognostic information for articular cartilage injuries. This data is adding to the orthopaedic community’s knowledge about cartilage injury and can help improve clinical decision-making.
Conclusions
Cartilage repair techniques have now evolved to make cartilage autotransplant and chondrocyte culture a viable and option for cartilage defects in the athlete. Obviously, patient selection remains the single most important factor for the results in cartilage repair studies. As seen in various trials and studies, patients with cartilage defects are not a uniform group, and this should be taken into consideration. Cartilage injuries in the athlete are commonly associated with other pathological conditions of the joint such as ACL ruptures and meniscal injuries and they need to be addressed primarily for improving outcomes.
Recommended Reading
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CellTrans™ System Components
