Arthroscopic treatment of flexion deformity after ACL reconstruction

Cyclops lesions associated with both bundles and selective bundle repair of the anterior cruciate ligament

BACKGROUND

The remnant of a ruptured anterior cruciate ligament (ACL) can increase the risk of impingement or a cyclops lesion, which can increase challenges to proper tunnel placement.

PURPOSE

To evaluate the prevalence of cyclops lesions after ACL reconstruction and to assess the difference in the incidence of cyclops lesions between single-bundle repair and selective bundle repair of the ACL.

MATERIAL AND METHODS

This retrospective study included 151 patients who were diagnosed with an ACL tear after knee joint magnetic resonance imaging (MRI) who underwent ACL reconstruction surgery. MRI diagnosis of cyclops lesion formation was made if a soft-tissue mass was seen anteriorly in the intercondylar notch near the tibial insertion of the reconstructed ACL, based on sagittal T2-weighted (T2W) imaging. The size of the cyclops lesions was recorded as the largest diameter on the sagittal T2W imaging.

RESULTS

A cyclops lesion was detected in 74 (38.5%) cases. Cyclops lesions were detected more frequently in cases with single-bundle repair of the ACL, but the results were not statistically significant (P = 0.609). Compared with selective bundle repair, cyclops lesions had a significantly higher prevalence in the posterolateral (PL) bundle repair than in the anteromedial (AM) bundle repair (P = 0.027) based on MR images at 6-12 months after surgery.

CONCLUSION

The incidence of cyclops lesions did not differ significantly in single-bundle repair and selective bundle repair of ACL. However, selective PL bundle repair of the ACL showed a significantly increased incidence of cyclops lesions compared with selective AM bundle repair.

Cyclops lesions are associated with altered gait patterns and medial knee joint cartilage degeneration at 1 year after ACL-reconstruction

In this exploratory study, gait analysis and quantitative MRI (QMRI) were used to assess biomechanical differences in patients that present with cyclops lesions at 12 months after ACL-reconstruction (ACLR). Thirty ACLR patients without and 10 ACLR patients with cyclops lesions underwent 3T MR T_1ρ mapping of the reconstructed knee joint prior to ACLR and at 12 months after ACLR, as well as a gait assessment during a fixed walking speed at 12 months after ACLR. Both external sagittal and frontal plane knee joint moments and joint moment impulses were calculated and assessed throughout the stance phase of gait. ACLR patients with cyclops lesions demonstrated a significantly greater (34% larger, p = 0.03) first peak knee flexion moment (KFM) and KFM impulse (42% larger, p = 0.05), compared to those without cyclops lesions, which may suggest an increased load during the loading response phase of gait. There were no differences (p > 0.05) in knee extension or adduction joint moments or moment impulses. ACLR patients with cyclops lesions demonstrated a significantly increased change in T_1ρ (ΔT_1ρ  = 4.7 ms, p = 0.03), over 12 months, within the central medial tibia. The results of the study suggest that ACLR patients with cyclops lesions demonstrate altered sagittal plane loading patterns which may be related to an increased rate of medial tibiofemoral cartilage degeneration at 12 months after ACLR. The first peak external KFM may be an important target for intervention programs in ACLR patients with cyclops lesions in order to possibly slow the onset or progression of medial tibiofemoral cartilage degeneration. © 2017 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 35:2275-2281, 2017.

Cyclops lesions detected by MRI are frequent findings after ACL surgical reconstruction but do not impact clinical outcome over 2 years

OBJECTIVES

To assess the impact of cyclops lesions with MRI in patients treated for anterior cruciate ligament (ACL) tears on clinical outcome.

METHODS

In 113 patients (age 29.8 ± 10.5y; 55 females; BMI 24.8 ± 3.7 kg/m²) with complete ACL tear, 3 T-MRI scans were obtained before, 6-months, 1-year (n = 75) and 2-years (n = 33) after ACL reconstruction. Presence and volume of cyclops lesions were assessed. Clinical outcomes were measured using the Knee injury and Osteoarthritis Outcome Score (KOOS) and differences between time points (∆KOOS) were calculated. Changes of KOOS subscales were compared between patients with and without cyclops lesion. KOOS was also correlated with lesion volume.

RESULTS

Cyclops lesions were found in 25% (28/113), 27% (20/75) and 33% (11/33) of patients after 6-months, 1- and 2-years, respectively. The lesion volume did not change significantly (P > 0.05) between time points, measuring 0.65 ± 0.59, 0.81 ± 0.70 and 0.72.9 ± 0.96 cm³, respectively. Clinical outcomes based on KOOS subscales were not significantly different in patients with cyclops lesions compared to those without cyclops lesions (each comparison P > 0.05), and no significant associations of clinical outcomes with lesion volume were found (P > 0.05).

CONCLUSIONS

Neither presence nor size of cyclops lesions within the first 2-years after ACL surgery were associated with inferior clinical outcome.

KEY POINTS

• Cyclops lesions had a prevalence of 25% in patients after ACL reconstruction. • Subjects with cyclops lesions did not have an inferior clinical outcome. • Cyclops lesions developed within the first 6 months after surgery. • The size of cyclops lesions did not significantly change over a period of 2 years.

Symmetric limb overgrowth following anterior cruciate ligament reconstruction in a skeletally immature patient

This report describes a case of symmetric femoral and tibial overgrowth of 2.8 cm in a 13-year-old patient after undergoing reconstruction surgery for his torn right anterior cruciate ligament. A literature review of previous cases is also provided. Following a pediatric anterior cruciate ligament tear, delaying surgery until the patient approaches skeletal maturity may avoid long-term growth disturbances, however, delaying this procedure may increase the probability of further joint damage. This growth disturbance was managed with a percutaneous epiphysiodesis that corrected the limb length deformity.

Prognostic factors of arthroscopic adhesiolysis for arthrofibrosis of the knee

Purpose

To assess the results of arthroscopic adhesiolysis for arthrofibrosis of the knee and to investigate possible prognostic factors.

Materials and Methods

Among the patients who developed arthrofibrosis after knee joint surgery, 68 patients who underwent arthroscopic adhesiolysis and were available for at least one-year follow-up were evaluated with regard to the Lysholm knee score, International Knee Documentation Committee (IKDC) subjective knee score, patient satisfaction, and range of motion (ROM) of the knee. The influence of possible prognostic factors including the cause of arthrofibrosis, duration of disease, and age of the patient on the postoperative ROM was analyzed.

Results

Sixty-one patients (89.7%) obtained an average increase of 48.6° in ROM; however, the remaining seven patients (10.3%) did not show any increase at the final follow-up. The Lysholm knee score and IKDC subjective knee score increased significantly at the final follow-up. Patient satisfaction was high or very high in 89.7% of the patients at the final follow-up. There was no association between the cause of arthrofibrosis and the increase in postoperative ROM. The duration of disease was significantly related to the postoperative recovery of ROM. Age had no significant influence on the postoperative recovery of ROM.

Conclusions

We believe that arthroscopic adhesiolysis is effective for the treatment of intraarticular arthrofibrosis. In particular, the duration of the disease had significant influence on the postoperative outcome.

The surgical treatment of knee stiffness following anterior cruciate ligament reconstruction

Knee stiffness following anterior cruciate ligament (ACL) reconstruction remains a common complication, which can substantially impair knee function. The aim of this study was to assess the effectiveness of arthroscopic arthrolysis, in conjunction with manipulation under anaesthetic (MUA), in treating stiffness post-ACL reconstruction. We reviewed the records of 18 patients who underwent arthroscopic arthrolysis to treat established stiffness following primary isolated ACL reconstruction. Eight of these patients underwent concomitant MUA at time of arthrolysis. The median time between reconstruction and arthrolysis was nine months. Seven patients had arthrolysis performed within eight months of reconstruction, while 11 patients underwent arthrolysis greater than eight months postreconstruction. Following arthrolysis, the mean extension loss improved from 7° to 1°. In patients with mild extension stiffness (prearthrolysis extension deficits <10°), the mean improvement to extension was 3°. In patients with severe extension stiffness (prearthrolysis extension deficit ≥10°), the mean improvement to extension was 10°. Arthroscopic arthrolysis was significantly more effective in restoring extension loss if carried out within eight months of the primary reconstruction (P < 0.03). In the patients who underwent MUA at time of arthrolysis, the mean flexion loss improved from 16° to 4°. In conclusion, arthroscopic arthrolysis, in conjunction with MUA, is an effective treatment for knee stiffness post-ACL reconstruction but ideally should be carried out within eight months.

MRI of Hoffa's fat pad

The infrapatellar fat pad of Hoffa is commonly injured but rarely discussed in the radiological literature. Abnormalities within it most commonly are the consequences of trauma and degeneration, but inflammatory and neoplastic diseases of the synovium can be confined to the fat pad. The commonest traumatic lesions follow arthroscopy, but intrinsic signal abnormalities can also be due to posterior and superior impingements syndromes and following patellar dislocation. Infrapatellar plica syndrome may also be traumatic in aetiology. The precise aetiology of ganglion cysts is not understood; the principal differential diagnosis is a meniscal or cruciate cyst. Hoffa's fat pad contains residual synovial tissue, meaning that primary neoplastic conditions of synovium may originate and be confined to the fat pad. Inflammatory changes along the posterior border of the pad may also be used to help differentiate effusion from acute synovitis on unenhanced MR examinations.

Progressive loss of knee extension after injury. Cyclops syndrome due to a lesion of the anterior cruciate ligament

Cyclops syndrome has been defined as a loss of knee extension due to impingement of a pedunculated proliferative tissue mass after anterior cruciate ligament reconstruction. We describe four patients who were operated on for progressive loss of knee extension after minor knee injury. During the arthroscopic procedure, the consistent finding was a fibrous pedunculated nodule adhering to the anterolateral aspect of the original anterior cruciate ligament, obstructing extension by impingement in the anterior aspect of the knee. At least part of the anterior cruciate ligament was intact in all cases. These patients were compared with seven patients who developed cyclops syndrome after anterior cruciate ligament reconstruction. Clinical and arthroscopic findings were the same in both groups. An arthroscopic excision of the nodule, performed an average of 12 weeks after knee trauma or after reconstruction, gave very good results. Histologic examination of the excised nodules from both groups showed fibroelastic connective tissue proliferation, thromboangiitis, and areas of necrotic bone and foreign body giant cell granuloma. On the basis of our observations, we conclude that formation of a fibrous pedunculated nodule may occur after an anterior cruciate ligament injury as well as after surgical reconstruction of the anterior cruciate ligament.

Cyclops syndrome occurring after partial rupture of the anterior cruciate ligament not treated by surgical reconstruction

Cyclops syndrome is one of the specific causes of loss of extension of the knee following anterior cruciate ligament (ACL) reconstruction. The syndrome is manifested by progressive loss of extension associated with pain and audible clunk at terminal extension caused by a pedunculated nodule of fibrovascular proliferative tissue usually arising from the graft. The entity has been described recently and has been reported exclusively as a complication of ACL reconstructions. We report the case of a patient with symptoms and arthroscopic and histological findings compatible with cyclops syndrome that developed after a partial ACL rupture that was not treated by surgical reconstruction. A different etiology and classical histological and immunohistological microscopic analysis of the nodule presented in this report may further clarify the pathogenesis of the cyclops syndrome.

MR imaging of cyclops lesions

OBJECTIVE

Localized anterior fibrosis (cyclops lesion) is a known cause of extension loss of the knee after anterior cruciate ligament (ACL) reconstruction. We describe MR imaging as a noninvasive diagnostic tool to examine cyclops lesions.

SUBJECTS AND METHODS

Thirty-three MR studies of 31 patients with residual persistent extension loss after ACL reconstruction using patellar tendon autograft were reviewed and compared with results of second arthroscopy. We used MR imaging to describe the ACL graft signal intensity and course, tibial and femoral tunnel placement. quantitative measurements of notch size and shape, and the presence or absence of cyclops lesions. When a cyclops lesion was revealed on MR imaging, the signal-intensity characteristics, location, and size were documented. Preoperative MR imaging findings were then correlated with findings at arthroscopy.

RESULTS

The sensitivity, specificity, and accuracy of revealing a cyclops lesion on MR imaging were 85.0%, 84.6%, and 84.8%, respectively. We found no statistically significant differences in the size of intercondylar notches for patients with and patients without cyclops lesions.

CONCLUSION

MR imaging was sensitive, specific, and accurate in revealing cyclops lesions in a subgroup of patients with extension loss after ACL reconstruction.

The long-term effects of tibial drill hole position on the outcome of anterior cruciate ligament reconstruction

Fifty-three cases of anterior cruciate ligament reconstruction were classified into two groups depending on the tibial drill hole position: in the anterior group, the center of tibial drill hole was positioned anteriorly to the dome of the intercondylar notch (Blumensaat's line), and in the posterior group, it was positioned posteriorly to the Blumensaat's line. Knee extension loss in the anterior group was significantly greater at 1 and 2 years postoperatively than that of the posterior group. However, there were no differences between the anterior and posterior groups 3 to 5 years postoperatively. No significant differences in anterior laxity were seen from 1 to 4 years postoperatively. After more than 5 years, anteroposterior translation of the anterior group was significantly greater than that of the posterior group. In the anterior group, extension was restricted in the early postoperative period. At latest follow-up more than 5 years postoperatively, anterior laxity in the posterior group was significantly less than that in the anterior group.

Classification and management of arthrofibrosis of the knee after anterior cruciate ligament reconstruction

We report 72 patients with disabling knee arthrofibrosis who were treated at our clinic. All patients had painful restriction of extension or limitation of both extension and flexion that had persisted despite physical therapy. The level of arthrofibrosis was categorized into one of four types: Type 1 (25 patients), < 10 degree extension loss and normal flexion; Type 2 (16 patients), > 10 degree extension loss and normal flexion; Type 3 (15 patients), > 10 degree extension loss and > 25 degree flexion loss with a tight patella; and Type 4 (16 patients), > 10 degree extension loss, 30 degrees or more flexion loss, and patella infera with marked patellar tightness. All patients were treated with outpatient arthroscopic surgery. Anterior scar resection down to the proximal tibia was required for all patients with Types 2, 3, and 4 arthrofibrosis. Notchplasty was performed when necessary. Medial and lateral capsular releases and knee manipulation were required for patients with Type 3 or 4 arthrofibrosis. Postoperatively, all patients with Types 2, 3, and 4 arthrofibrosis were treated with outpatient serial extension casting. At the time of latest followup (28 to 115 months), the mean improvement of range of motion was as follows: Type 1, 7 degrees of extension; Type 2, 14 degrees of extension; Type 3, 13 degrees of extension and 28 degrees of flexion; and Type 4, 18 degrees of extension and 27 degrees of flexion. Improvement was also found for the mean stiffness, self-evaluation, functional activity, and Noyes knee scores in all groups.

Stiffness of the knee--mixed arthroscopic and subcutaneous technique: results of 67 cases

This study is an analysis of the treatment for mixed-cause stiffness of the knee: intraarticular and extraarticular. We examined 67 patients. The cause of stiffness was mostly ligamentous surgery, found in 51 cases (76%). Preoperative range of motion was 11 degrees extension and 89 degrees flexion. In 14 cases extension was complete. In the remaining 53 cases, extension was limited. Results achieved with arthroscopic arthrolysis were generally excellent. The ideal time to perform the operation is within the first 9 months after injury. The best results were obtained in the 7th month. Results deteriorate notably after 1 year. The age of the patient does not seem to affect the end result.