|
 
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| REVIEW ARTICLE |
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| Year : 2016 | Volume
: 16
| Issue : 1 | Page : 1-6 |
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Recent concepts of rehabilitation following anterior cruciate ligament reconstruction
Naiyer Asif, Rahul Ranjan, Sohail Ahmad, Latif Zafar Jilani
Department of Orthopaedic Surgery, J. N. Medical College, Aligarh Muslim University, Aligarh, Uttar Pradesh, India
| Date of Web Publication | 7-Jan-2016 |
Correspondence Address:
Rahul Ranjan
Department of Orthopaedic Surgery, J. N. Medical College, Aligarh Muslim University, Aligarh - 202 002, Uttar Pradesh
India
 Source of Support: None, Conflict of Interest: None  | Check |
DOI: 10.4103/1319-6308.173470
Anterior cruciate ligament (ACL) reconstruction is the most common ligament reconstruction done till date. The tendency has inclined toward the surgical reconstruction from conservative means. In this review article, we will discuss the phases of the rehabilitation of the patient following the surgical reconstruction of the ACL. Importance will be given especially on early return of passive motion, early weight bearing, bracing, kinetic chain exercises, neuromuscular drill, and accelerated rehabilitation. There are many young individual who are not recovering enough to regain the preinjured level of activities. In this review article, we will present some of the recent evidences regarding ACL rehabilitation in an effort to help the hectic surgeons and physiotherapist comprehend and associate basic and clinical research to rehabilitation of a patient following reconstruction.
المفاهيم الحديثة لإعادة التأهيل بعد إعادة الإعمار في الرباط الصليبي الأمامي
تعدّ عملية إعادة إعمارالرباط الصليبي الأمامي (ACL) وإعادة بناء الرباط الأكثر شيوعا حتى الآن. ويعد الاتجاه نحو إعادة الإعمار الجراحي من وسائل المحافظة.
في هذه المقالة ، وسوف نناقش مراحل إعادة تأهيل المريض بعد الإعمار الجراحي للرباط الصليبي الأمامي ACL. وسنولى أهمية خاصة للعودة المبكرة للحركة السلبية، و الوزن في وقت مبكر، و تمارين السلسلة الحركية،و العصبية والعضلية و
الحفر، وتسارع إعادة التأهيل.
هناك العديد من الشباب الفرد الذي لا يتعافى بما يكفي لاستعادة مستوى ما قبل الإصابة من الأنشطة.
في هذه المقالة ، سنقدم بعض الأدلة الأخيرة فيما يتعلق بإعادة تأهيل الرباط الصليبي الأمامي ACL في محاولة لمساعدة الجراحين وأخصائي العلاج الطبيعي و كذلك المهتمين بالبحوث الأساسية والسريرية لإعادة تأهيل المريض بعد إعادة الإعمار.
Keywords: Anterior cruciate ligament, physical therapy, rehabilitation
How to cite this article:
Asif N, Ranjan R, Ahmad S, Jilani LZ. Recent concepts of rehabilitation following anterior cruciate ligament reconstruction. Saudi J Sports Med 2016;16:1-6 |
How to cite this URL:
Asif N, Ranjan R, Ahmad S, Jilani LZ. Recent concepts of rehabilitation following anterior cruciate ligament reconstruction. Saudi J Sports Med [serial online] 2016 [cited 2023 Mar 21];16:1-6. Available from: https://www.sjosm.org/text.asp?2016/16/1/1/173470 |
| Introduction | |  |
Reconstruction of the injured anterior cruciate ligament (ACL) is a common surgical procedure with reports ranging from 100,000 to 300,000 reconstructions performed annually.[1],[2] The ACL is the key stabilizer for anterior tibial translation and the secondary stabilizer for tibial internal rotation. Knee with ACL insufficient leads to articular cartilage damage, meniscal tear and change in knee kinematics, and finally early osteoarthritis.[3],[4] The primary role of physical rehabilitation of a patient following ACL rehabilitation is to return back to their preinjured functional level. This becomes, especially important due to muscular strength deficiency is seen following ACL reconstruction for up to 2 years postsurgery.[5],[6] Due to improvement in the fixation methods, the rehabilitation progression has changed dramatically. Now, the patient can be permitted for sports activities, as early as, 8 weeks postsurgery.[7],[8] Postoperative physical therapy protocol speed up an athlete to return to sports level of activities safely.
In this review article, we will talk about the rehabilitation opinion of ACL reconstruction using an autograft, especially hamstring and bone patella tendon bone (BPTB), as these are the most commonly used and consider the gold standard. Many studies have been done recently shown only minor clinical and functional differences in outcomes between BPTB and four-stranded semitendinosus/gracilis tendon autografts.[3],[4],[9]
Associated pathologies such as concomitant other ligament surgery, meniscus, or articular cartilage injury will need to be taken into consideration and will more likely retard in progression.
Ligamentization
Following an ACL reconstruction, the graft passes through a process which is called ligamentization. There are different stages of ligamentization including: (a) Necrosis, (b) revascularization, (c) cellular proliferation, and (d) collagen formation.[10] Very early following reconstruction necrosis of the graft tissue occurs. For the survival of the graft, requires a blood supply and early during the first several weeks are nourished by bone blood and synovial fluid.[11] Revascularization follows the phase of necrosis. It usually starts at approximately 6–8 weeks postoperatively. Animal studies have shown that graft is at its weakest point at 6–8 weeks postreconstruction, and hence, controlled loading of the ligament is advisable for healing, whereas excessive stress loading may elongate the graft leading to unwanted anteroposterior laxity.[12] In the phases of cellular proliferation cells other than the native graft tissue may inhabit the graft. Usually, at the end of 30 weeks the posttransplanted graft will have tissue characteristics that appear ligamentous. Collagen formation continues for more than 1-year.[13]
| Postoperative 0–4 weeks (Phase I) | | |
A proper compliance of the patient to the given advice is the most crucial part of any type of therapy. Hence, on the first visit clear instructions related to any information about the rehabilitation schedule will help to enhance self-efficacy and ease concerns. Education about postsurgery exercises, reasons for the limited motion and crutch use and cryotherapy all will help kindle early functional recover of knee function, and facilitate the patient appreciates the importance of the rehabilitation process in general.[14],[15],[16] Soon after, surgery the initially all attempt is considered to minimize pain and swelling and to return the full extension of the knee. It is advisable to achieve knee flexion up to 90–120°. In case of isometric placement of the graft, the even full range of motion does not stress the graft.
Following surgery swelling and pain, both are a part of the normal inflammatory response to begin the healing process. Alteration in quadriceps motor firing and the range of motion occurs due to pain and swelling, and hence cryotherapy and electrical stimulation are encouraged early. Intraarticular swelling mainly due to hemarthrosis (seen in 12% of post-ACL patients) can have unfavorable effects on the articular cartilage and synovium if it remain for prolong period.[17] Cryotherapy stimulates the release of endogenous opiates and inhibiting nerve conduction velocity in those with painful knee following ACL reconstruction.[18] It is also helpful in the disinhibition of quadriceps muscle.[19],[20]
Early randomized controlled trials on immobilization versus delayed range of motion demonstrated significant atrophy of the vastus lateralis and slow twitch muscle fibers with no adverse effect on graft laxity.[21],[22],[23],[24],[25] Since, joint immobilization for prolonged time frames results in loss of ground substance and dehydration and approximation of fibers embedded in the extracellular matrix, the range of motion of the knee should be started early.[24],[25] Even a bit loss of 3–5° of extension can dramatically affect outcomes following cruciate reconstruction.[26] The complete extension also ensures that the intracondylar notch is not proliferated with scar tissue, resulting in the development of cyclops lesion. The extension lag can be particularly deleterious, as it results in abnormal joint kinematics at both the tibiofemoral and the patellofemoral joints leading to aberrant cartilage contact pressures, and the quadriceps muscle insufficiency due to pain and fatigue.[27],[28]
If knee extension lag persist, selected exercises can be helpful. The manual passive range of motion into hyperextension, static quadriceps drill, prone hangs, can all be used to make passive knee extension force.[16],[29] If the posterior capsular contracture is causing limitation in the extension of the knee, plastic deformation of the capsular structure can be achieved by a long-duration prolonged stretch. Allowing the knee to fall into an extension for up to 20 min while the patient is in either prone or supine is good to create low-load, capsular stretching.
As far as active heel slide is concerned, after BPTB reconstruction active heel slides are advised. In case of hamstring tendon ACL reconstruction, active heel slide is discouraged up to 3–4 weeks for donor site healing, but wall slide or passive knee flexion should be encouraged.
Patellofemoral scarring is seen more commonly with the BPTB reconstruction,[30] and it decreases the mobility of the patellar. Patellofemoral scarring can be treated with immediate patellar mobilization in all directions, especially in superior-inferior direction for the extensor mechanism to function efficiently. Superior patellar glide mobilizations improve knee extension while inferior patellar glides assist with knee flexion.
Due to the effects of asymmetrical limb loading early weight bearing is done with bilateral axillary crutches.[31],[32] Weight bear is encouraged from, as much as tolerated immediately, to full weight bear at the end of 1–2 weeks. Weight bearing may be delayed in those with concomitant articular cartilage repair or meniscus repair, which may not tolerate the increased stress of full weight bearing.
For the function of the knee, motor control, and function of the muscles around the knee are required. With the BPTB reconstruction, the extensor mechanism insult during graft harvesting is significant. In order to lessen entrapment of scar tissue, early active contraction is essential. It also squeezes the anterior knee soft tissue and decreases the swelling.[33] In many studies, the high-intensity electrical stimulation has been proved to improve the quadriceps strength and the gait parameter.[3],[4],[34],[35] It is warranted if there is decline quadriceps tone firing after 2–3 visits.
Other quadriceps exercise comprise isometric contractions with the knee in a position of a quadriceps set, straight leg raise, or within safe ranges of 90–45° of knee flexion. If the patient has a problem in performing supine terminal knee extension, they can perform this exercise in the prone position with hip extensors aiding achievement of full extension.[36]
As the replaced graft is passing through a process of necrosis in Phase I, the graft should be protected. Protected exercises at this time include isometric quadriceps drill, straight leg raises exercise, closed kinetic chain (CKC) leg press, shuttle or squats (0–60°), and open kinetic chain extension (90–40°).
The role of the knee brace in postoperative rehabilitation is debatable. Bracing during the early phases appears to reduce swelling and pain, but at long-term follow-up, there is no considerable effect on the clinical outcome.[37],[38],[39] Once the patient, attain good quadriceps strength with the ability to perform straight leg raise without extensor lag they may be allowed to put an end to the brace. In the case of extensor lag of more than 5° they may be advised to continue to use brace during sleeping with the brace locked in extension.
| Postoperative 4–6 weeks (Phase II) | | |
During this short period of rehabilitation main aim is to normalize the gait. The loss of extension is suggestive of arthrofibrosis, hence any loss of extension should be treated uncompromisingly, and manipulation under anesthesia or arthroscopic debridement if required. Flexion should be expectant to full if restricted. The sometime effusion may hinder range of the motion, quadriceps control, and altered gait can be minimized using cryotherapy.
Sometimes, the altered gait may be unconscious in nature. The use of a mirror can view themselves and their altered gait can be helpful. A useful drill is instituted, when the athlete is still walking with a stiff knee that lacks flexion following toe off is the high-stepping drill.
During this phase of rehabilitation, the necrosis phase of graft healing commences, and the revascularization started. The isometric exercises can be shifted to isotonic and slowly allow increased stress to the knee allowing greater graft strength during incorporation.
Quadriceps strengthening can be shifted from wall slides to mini-squats or progressive resistive leg press exercises. Heel raises can begin now unilaterally while balance and proprioceptive exercises can include weight shifting bilaterally with progressions to unilateral if tolerated. If a hamstring autograft was utilized, gentle submaximal isometric could be started, whereas hamstring strengthening exercise can be started if BPTB was used as graft material.
Strengthening of the hamstring muscles in this phase may provide a primary dynamic restraint to anterior tibial translation.[40] The ACL-mechanoreceptor reflex arc to the hamstrings may lead to loss of proprioception, as the hamstrings are almost twice latent as that of the normal contralateral uninjured knee.[41] By this time, healing of donor site of hamstring completed and hence gentle hamstring and gastrocnemius and soleus flexibility and strengthening exercises can be encouraged.
CKC squats can be started beginning on a stable surface with progressions to the unstable or labile surface. The athlete is allowed to flex the knees to approximately 25–30° and maintain that position, as it produces a co-contraction of the hamstrings, and quadriceps.[42] Squatting on the medial/lateral or anterior/posterior tilted board is encouraged. It can be added with proprioception exercises like perturbation force by taping on the board in different locations. It has found to decrease the frequency of giving way episodes following ACL injury.[43]
| Postoperative 6 weeks to 3 months (Phase II) | | |
The main goal of this phase is to encourage the patient to basic functional activities to a tolerance of those more advanced activities that allow them to progress to full recreational or sporting activities at much higher levels.
The main concern is the evidence that the autograft is the weakest at this point of time (6–8 weeks).[12] There are evidence that the actual graft may only reach between 11% and 50% failure load of the native ACL at the 1-year point.[44] It is theorized that the controlled loading will enhance ligament and tendon healing, but excessive stress loading to an ACL graft may cause graft undue elongation leading to excessive unwanted anterior-posterior laxity.[45],[46],[47]
During this period, the patient should have a full range of motion of both knee extension and flexion. The basic functional activities should be painless and without any discomfort. At the end of 12 weeks, one should have adequate strength and balance to allow progression of controlled individual sports and recreational activities.
The progressive resistive isotonic knee extension exercises in the range of 90–45° should be started. This range can be done both concentrically and eccentrically. Single leg squats and unilateral leg press in the range of 0–45° can be done safely. At 12 weeks, as long as the satisfactory exam is performed, the patient is progressed to higher functional activities.
| Postoperative 3–6 months (Phase IV) | | |
In this phase, patient readies themselves for a gradual progression to full unhindered physical or sporting activities. In case, if clinical examination shows no any abnormal findings they are allowed to start straight in-line jogging. Exercises that stress single-limb postural control are given first on level or stable ground and then progressed to an unstable or labile surface.
To maintain the center of mass, balance, and postural control core stability is required. To enhance core stability exercise for the trunk and hips is required. Consensus is in the favor of restoring core strength and stability, a reduction of injury risk may occur due to the more effective control of athletes center of mass during higher level activities.[48],[49],[50] Core training consist of multiple exercises for the core include bridging exercises, sit-ups, single leg bridges, straight leg dead lifts, and planks, etc., All exercise progression for the lower extremities should begin bilaterally and progress to unilateral loading.
Increased progression of single limb balance can include balance with eyes closed, moving ahead to the entire balance progression (single limb stance on a flat level surface, while moving the contralateral extremity through classic movement patterns such as flexion/extension, abduction/adduction) being done on a labile or unstable surface. These types of training are considered to be beneficial for enhancing balance and proprioception. Their use for objective evaluation may be difficult to assess by a clinician, as they may not be sensitive enough to determine, deficits following ACL reconstruction.[51]
| Postoperative More Than 6 months (Phase V) | | |
In this final phase of the rehabilitation, the patient may be released for full return to functional activities. It must be noted that during this time athletes will start to expose their knee to forces and motions that may load the reconstructed graft to near it limits.[52],[53] At present, there are less evidences, as to when it is safe to return to sports participation.[54],[55],[56] There are a several forms of judgment for determining return to play such as an isokinetic strength test, jumping, hoping, and agility test. As no single test (strength or function) has been proven to be superior, return to full unlimited sports participation is often based on physician and therapist preference for the testing method rather than evidence-based science. Recently, biomechanical data recommend that altered neuromuscular control of the hip and knee during a dynamic landing task, as well as postural stability deficits, after ACL reconstruction are predictors of a second ACL injury after an athlete has returned to sports.[57]
In this phase rehabilitation exercises should utilize the concept of overload to develop strength and power in the athlete yet at the same time are within a level of acceptance to create minimal exposure to potential injury risk of re-rupture of the still maturing graft. In this final stage of rehabilitation activities that require unique aspects of their respective sport can be used in treatments. Those activities that require the high power generation, change of direction and cutting, may be the priority. In addition to the previous described exercises, athletes can now perform in a controlled environment exercises like higher level plyometric exercises including bilateral box jumps (jumping to the box) performed in both anterior and lateral directions, higher level lateral bounding, single-leg box jumps (hopping to the box) performed both anterior and lateral, power skipping, zigzag bounding, and scissor-jumps, etc.
| Conclusions | | |
The main goal is to attain full unrestricted functional activities at the end of rehabilitation. Immediate postoperatively main focus is to decrease swelling and pain. Gradually, the improvement in the range of motion and strengthening quadriceps motor control is done. A gradual progression of increased stress is applied to the knee and lower extremity through these five phase rehabilitation program. Rehabilitation following ACL reconstruction should be based on the best clinical evidences available.
Financial support and sponsorship
Nil.
Conflicts of interest
There are no conflicts of interest.
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