A study of clinical outcome following arthroscopic posterior cruciate ligament reconstruction

 

 

Abstract               Background: Knee joint is a primary weight bearing joint, commonly injured in accidents, sports activity. Posterior Cruciate Ligament (PCL) injuries are not so common, can occur in isolation or in combination with other knee joint injuries and prone to be easily missed without a high index of suspicion. Studies reported Posterior cruciate ligament (PCL) injuries in 1% to 40% of all acute knee injuries, of mostly associated with multi-ligamentous knee injuries. The purpose of the present study was to evaluate the surgical outcome of arthroscopic PCL reconstruction. Material and Methods: This retrospective and descriptive study was conducted in patients undergoing arthroscopic PCL reconstruction. Results: 18 patients were included in this study. Common age group was 21 to 35 years (67 %) and PCL injuries were common in men (94 %). Combined injuries were 67 % while isolated injuries were 33 %. High number of isolated injuries is mainly due to high suspicion, experienced radiologists in knee injury. As per Knee Dislocation Schenck classification type I, II, III, IV fractures were 33%, 39%, 17%, 11% respectively. There were significant improvements from preoperative to 1-year follow-up in KOOS (KOOS (Knee injury and Osteoarthritis Outcome Score) scores, Tegner activity score, IKDC subjective and objective outcome scores. Conclusion: Patients with both isolated and combined PCL reconstructions had improved in terms of stability and subjective knee function after surgical management.

Key Words: PCL reconstruction; knee; arthroscopy

 

INTRODUCTION

Knee joint is a primary weight bearing joint, commonly injured in accidents, sports activity. Posterior Cruciate Ligament (PCL) injuries are not so common, can occur in isolation or in combination with other knee joint injuries and prone to be easily missed without a high index of suspicion. Studies reported Posterior cruciate ligament (PCL) injuries in 1% to 40% of all acute knee injuries, of mostly associated with multi-ligamentous knee injuries. The complex anatomy of the PCL consists of two bundles based on the ligament function in flexion and extension^2,3,4. The anterolateral bundle which accounts for at least 2/3 of the entire PCL, it is the primary restraint for maintaining the posterior stability of tibia at 0°–120° of flexion. Posteromedial bundle maintains the posterior stability of tibia at hyperextension and flexion over 120°.

Improvements in understanding of biomechanics of PCL and its insufficiency, advanced diagnostic tests like MRI and high suspicion have improved diagnosis of these injuries. Management of injuries to the PCL has been evolving from conservative management to selective surgical management⁵. The proximal avulsion tears can be treated with arthroscopic primary repair^6,7, whereas mid substance tears are generally treated with PCL reconstruction⁸, distal bony avulsion can be treated with internal fixation⁹. Initially open primary repair was the preferred treatment of PCL injuries⁹. Deep location, complex joint anatomy forced to develop minimal invasive approaches like micro endoscopy-assisted and arthroscopic techniques⁹.The goal of arthroscopic primary repair is the preservation of the native PCL using a minimally invasive method and subsequent protection of this repair using suture augmentation. The purpose of the present study was to evaluate the surgical outcome of arthroscopic PCL reconstruction.

 

MATERIAL AND METHODS

This retrospective and descriptive study was conducted in Department of Arthroscopy and sports medicine, Baby memorial hospital Calicut, Kerela. Patients underwent arthroscopic reconstruction of posterior cruciate ligament during January 2016 to Dec 2018 (3-year period). As a retrospective study, permission to review records was obtained from concerned authority. Department has kept separate follow up record for arthroscopic PCL reconstruction patients, which proved useful. Data combined from indoor papers and follow up records. Detailed history, physical examination findings, investigations like MRI knee, operative details, postoperative outcome were documented. The pre-operative evaluation had a mandatory MRI knee. All patients were operated by senior faculties. Complete 1-year follow-up was considered, follow up taken by senior surgeon with a standardized objective clinical examination and subjective scoring such as validated KOOS score¹⁰, International Knee Documentation Committee [IKDC] score. Knee joint functionality and activity level was assessed by Tegner activity score¹¹. All data was collected in Microsoft excel sheet and analysed accordingly.

 

RESULTS

PCL injuries are not so common, during study period we had total 19 patients, arthroscopically operated for repair of PCL. One patient has not completed follow-up till one year, so 18 patients were included in this study. Due to factors as uncommon nature of injury, patient number is less. Common age group was 21 to 35 years (67 %) and PCL injuries were common in men (94 %). Outdoor activity and travelling is more common in males, more exposure to trauma may be the cause for male predominance. High‑velocity trauma in road traffic accident was the most common mode of injury noted in our study. Combined injuries were 67 % while isolated injuries were 33 %. High number of isolated injuries is mainly due to high suspicion, experienced radiologists in knee injury. As per Knee Dislocation Schenck classification type I, II, III, IV fractures were 33%, 39%, 17%, 11% respectively.

Table 1: General characteristics

KD, knee dislocation: ACL, anterior cruciate ligament; PCL, posterior cruciate ligament; PMC, posteromedial corner; PLC, posterolateral corner

 

 

 

 

 

Table 2: Evaluation

 

 The standard PCL reconstruction procedure was arthroscopic double-bundle reconstruction with fixation at the tibial side with bioabsorbale screw and femoral fixation with endobutton, while ACL reconstruction done by with graft in the native ACL footprint. Standard post-operative care was provided. Hinged brace provided for 8 weeks. For first 6 weeks, non-weightbearing was advised and the brace was fixated in 0 to 20 degree of flexion. Next 2 weeks, weightbearing activities initiated and gradually increased. We noted minor superficial infection in two patients, managed conservatively. Regular follow up was taken at 3,6,9 and 12 months. There were significant improvements from preoperative to 1-year follow-up in KOOS (KOOS (Knee injury and Osteoarthritis Outcome Score) scores, Tegner activity score, IKDC subjective and objective outcome scores.

DISCUSSION

In India, most of daily living habits such as squatting, sitting cross leg requires extreme flexion at knee joint. Trauma to knee joint increased in recent 10-20 years. Use of 2-wheeler motorcycles, other road traffic accidents, sports activities are main causes of trauma to knee joint. Knee joint injuries are challenging to the orthopedic surgeons because of their variety, complexity, different concepts of management and injuries associated with it. Post-trauma knee fractures are known to cause varying degrees of limitation in knee movements. Conservative treatment results in knee stiffness, due to joint line incongruity and early osteoarthritis. Surgical anatomic reduction and fixation has reduced incidence of osteoarthrosis. Ligament injuries are common in knee joint and difficult to diagnose because of multilimbed injuries, complex anatomy, prone to be missed easily, anatomically difficult location, etc.The posterior cruciate ligament (PCL) is an important structure, plays important role in maintaining knee joint stability during flexion and rotation. Since the PCL is strong structure, injuries are not so common, if present many times associated with other ligament injuries. Ideally PCL injuries should be anatomically reduced and fixed for complete restoration of PCL function¹². Conservative treatments in such cases had unsatisfactory results mainly due to functional disability and fracture nonunion¹³. Many surgeons believe the displaced or unstable tibial avulsion fracture of PCL should be reduced and fixed anatomically through surgeries with various techniques¹³. Surgical treatments for PCL injuries include arthroscopic repair as well as open reduction and internal fixation. Each procedure had their own advantages and disadvantages, basically type of surgery depends on factors such as presence of other injuries (ligaments, tibial), movements required at knee joint, availability of endoscopy facilities, skill of surgeon, financial and other factors. Open reduction and fixation are traditional approach, technically easier than arthroscopic surgery, does not have requirement for specialized equipment, has a relatively short learning curve¹⁴; whereas it has a potential risk of significant soft tissue damage and neurovascular damage, as the tibial attachment of PCL is located in an area difficult to access¹⁵. Recently, due to its deep location and the complexity of the adjacent anatomy, minimally invasive arthroscopic techniques are gaining interest¹⁶. The additional advantages of the arthroscopic approach are direct visualization of fragment reduction and concomitant intra-articular injuries in the form of meniscal tears; further, osteochondral loose fragments or ligament injuries may be addressed at the time of the operation¹⁷. Despite comparable biomechanical properties of open and arthroscopic techniques, there is a paucity of comparative clinical studies (open vs. arthroscopic) in the literature.

 

CONCLUSION

Patients with both isolated and combined PCL reconstructions had improved in terms of stability and subjective knee function after surgical management. There are still controversies surrounding PCL reconstruction techniques, and the current literature is lacking in that.

REFERENCES