Knee Stiffness After ACL Reconstruction

Abstract

Postoperative knee stiffness after anterior cruciate ligament reconstruction surgery is a significant clinical problem. Clinical deficits of knee flexion more than 10 degrees can limit function and athletic performance, and extension deficits of more than 5 degrees can cause gait changes and altered knee kinematics. The incidence reported in the literature varies significantly. Risk factors for the development of this condition include technical factors, graft selection issues, the timing of surgery relative to the traumatic injury, the presence of associated injuries, and postoperative rehabilitation. This chapter will review the incidence, risk factors, pathology, prevention, treatment options, and the clinical results of management of this condition.Key Words: anterior cruciate ligament reconstruction, single-bundle anatomic ACL reconstruction, knee stiffness, arthrofibrosis of the knee, physical therapy (Tech Knee Surg 2012;11: 26-33) K nee stiffness continues to represent one of the most common complications after anterior cruciate ligament (ACL) reconstruction surgery. This complication is of particular importance as stiffness after ACL reconstruction results in inferior functional outcomes and a higher incidence of radiographic evidence of arthritis. Knee stiffness presents as loss of motion and can include loss of extension, loss of flexion, or both. Normal knee range of motion (ROM) is from 5 degrees of hyperextension to 140 degrees of flexion. Deficits of > 10 degrees of flexion can limit athletic performance. Extension loss is poorly tolerated, with deficits of 5 degrees or greater producing gait changes, altering quadriceps function, and leading to patellofemoral arthritis. Prevention of knee stiffness after ACL surgery remains essential and requires a thorough understanding of the potential causes of loss of motion in ACL reconstruction. The treatment of loss of motion after ACL reconstruction requires an understanding of these causes and the pathoanatomy of the stiff knee. In addition, a systematic approach toward treatment of specific anatomic structures associated with the different types of motion loss is required for effective management. This article reviews the incidence, classification, risk factors, pathoanatomy, prevention, and treatment of knee stiffness after ACL reconstruction. EPIDEMIOLOGYThe true incidence of knee stiffness after ACL reconstruction is difficult to estimate as different studies have used different criteria for loss of motion and estimates have ranged from 2% 1 to 35%. 2 In a recent publication, Paxton et al 3 reported on one of the largest series of ACL reconstructions to date. In their prospective series of 4025 primary ACL reconstructions, the authors reported an overall reoperation rate of 4.4%. Knee stiffness was the second most common cause for reoperation (18.9% of reoperations) after meniscal/chondral injury (34.3% of reoperations), confirming that stiffness is one of the most common complications after ACL reconstruction.Stiffness of the knee after ACL recons...

Persistent knee extension deficits are common after anterior cruciate ligament reconstruction: a systematic review and meta-analysis of randomised controlled trials

“…While the degree of extension at early follow‐up (4 weeks) was determined to be strongly coupled with the incidence at later phases of recovery (12‐week follow‐up) [59], the true incidence of deficits are difficult to ascertain due to a lack of consistent criteria and poor definitions for determining loss of knee range of motion (ROM) [15]. Incidence of knee stiffness after surgical reconstruction of the ACL ranges from 2 to 35% [57], while loss of extension is also varied. A recent study of 229 patients reported 25.3% incidence at four weeks follow‐up [46], while others [63] report up to 59% incidence of extension loss following ACLR.…”

Incidence and prognostic factors of knee extension deficits following anterior cruciate ligament reconstruction: A systematic review and meta-analysis of randomised controlled trials

“…Knee stiffness, presenting as either loss of extension and/or loss of flexion, is a common presentation following acute ACL injury and reconstruction, resulting in poorer functional outcomes and greater incidence of osteoarthritis 6 . Loss of knee extension is less tolerated than flexion loss, and contributes to limitations in athletic performance, functional deficits and increased risk of patellofemoral arthritis at extension deficits of 5 degrees or more 6,7 . The aetiology for loss of extension (LOE) is multifactorial, ranging from anterior-intercondylar notch scar tissue or graft impingement, capsulitis, technicalities of the surgery and choice of rehabilitation protocol 7 .…”

“…Complications following ACL reconstruction (ACLR), though rare, can include missed concomitant injuries, tunnel malposition, infection, tunnel osteolysis, fixation failure, fracture, increased knee stiffness, graft site morbidity, and thromboembolic events 4,5 . Knee stiffness, presenting as either loss of extension and/or loss of flexion, is a common presentation following acute ACL injury and reconstruction, resulting in poorer functional outcomes and greater incidence of osteoarthritis 6 . Loss of knee extension is less tolerated than flexion loss, and contributes to limitations in athletic performance, functional deficits and increased risk of patellofemoral arthritis at extension deficits of 5 degrees or more 6,7 .…”

“…While the degree of extension at early follow-up (4 weeks) was determined to be strongly coupled with the incidence at later phases of recovery (12 weeks follow-up) 10 , the true incidence of deficits are difficult to ascertain due to a lack of consistent criteria and poor definitions for determining loss of knee range of motion (ROM) across the literature 9 . The reported incidence of knee stiffness after surgical reconstruction of the ACL ranges from 2-35% 6 , with one retrospective study of 100 patients reporting the incidence of knee stiffness at 12% 6 months following ACL reconstruction 11 . Specific incidence of loss of extension is also varied.…”

Recovery of knee extension and incidence of extension deficits following anterior cruciate ligament injury and treatment: a systematic review protocol

“…LOE in this context has a complex aetiology, ranging from soft-tissue fibrosis, capsular adhesions, or technical errors during surgery (e.g., tunnel misplacement) leading to graft impingement [8]. Other generalisable risk factors include involvement of other knee structures, preoperative range of motion, and poor rehabilitation compliance [5].…”