Motion loss after ligament injuries to the knee. Part I: causes

Surgically treated acute knee dislocations with knee stiffness perform equally as well as non-stiff knees when treated with arthroscopic arthrolysis

PURPOSE

Postoperative knee stiffness is a common issue in multiligament knee injuries (MLKIs). This study aims to compare outcomes between MLKI patients who underwent postoperative arthroscopic lysis of arthrofibrosis (LOA) for limited range of motion (ROM) and those who did not.

METHODS

Thirty-one patients (10 IIIM, nine IIIL and 12 IV) were included in this retrospective clinical study with acute type III or IV knee dislocations, while two patients were lost to follow up. Thirteen patients underwent LOA at a mean of 18.7 ± 8.4 weeks (Group A), while 18 did not require this intervention (Group B). Patient-reported outcome measures (IKDC, Lysholm, VAS) and ROM were evaluated.

RESULTS

The average follow up period was 31.0 ± 10.2 months. The mean time to LOA was 19.4 ± 7.6 weeks and a significant increase in ROM was observed after LOA (flexion: before LOA: 83.8° ± 19.2, after LOA: 119.6° ± 9.9; P < 0.0001). There were no significant differences between groups regarding clinical scores (Lysholm: Group A 85.0 ± 13.4, Group B 84.6 ± 14.5; IKDC: Group A 74.3 ± 10.8, Group B 76.7 ± 14.7) and ROM (flexion: Group A 118.6° ± 9.8, Group B 124.3° ± 12.8). There were no complications regarding LOA.

CONCLUSIONS

Patients, whether undergoing LOA or not, performed equally well in terms of ROM and clinical scores at final follow up, while timing of LOA appears less critical. LOA is a simple, durable and safe method of treating ROM deficits in patients treated for acute knee dislocation, with very good results.

Long-term effects of non-weight bearing and immobilization after anterior cruciate ligament reconstruction on joint contracture formation in rats

PURPOSE

Non-weight bearing improves and immobilization worsens contracture induced by anterior cruciate ligament reconstruction (ACLR), but effect persistence after reloading and remobilization remains unclear, and the combined effects of these factors on ACLR-induced contracture are unknown. We aimed to determine 1) whether the effects of short-term (2-week) non-weight bearing or immobilization after ACLR on contracture would be sustained by reloading or remobilization during a 10-week observation period, and 2) how the combination of both interventions compared to the outcome of either alone.

METHODS

We divided 88 ACL-reconstructed male rats into four groups: non-intervention, non-weight bearing, joint immobilization, and both interventions. Interventions were performed for 2 weeks, followed by rearing without intervention. Twelve untreated rats were used as controls. At 2, 4, and 12 weeks post-surgery, we assessed range of motion (ROM) and histological changes.

RESULTS

ACLR resulted in persistent loss of ROM, accompanied by synovial shortening, capsule thickening, and osteophyte formation. Two weeks of non-weight bearing increased ROM and reduced osteophyte size, but the beneficial effects disappeared within 10 weeks after reloading. Two-week immobilization decreased ROM and facilitated synovial shortening. After remobilization, ROM partially recovered but remained below non-intervention levels at 12 weeks. When both interventions were combined, ROM was similar to immobilization alone.

CONCLUSIONS

The beneficial effects of 2-week non-weight bearing on contracture diminished within 10 weeks after reloading. The adverse effects of 2-week immobilization on contracture persisted after 10 weeks of remobilization. The effects of the combined use of both interventions on contracture were primarily determined by immobilization.

Post-operative protein supplementation following orthopaedic surgery: A systematic review

Decreased mechanical loading after orthopaedic surgery predisposes patients to develop muscle atrophy. The purpose of this review was to assess whether the evidence supports oral protein supplementation can help decrease postoperative muscle atrophy and/or improve patient outcomes following orthopaedic surgery. A systematic review was conducted according to the Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA). PubMed (MEDLINE), Embase, Scopus, and Web of Science were searched for randomized controlled trials that assessed protein or amino acid supplementation in patients undergoing orthopaedic surgery. Two investigators independently conducted the search using relevant Boolean operations. Primary outcomes included functional or physiologic measures of muscle atrophy or strength. Fourteen studies including 611 patients (224 males, 387 females) were analyzed. Three studies evaluated protein supplementation after ACL reconstruction (ACLR), 3 after total hip arthroplasty (THA), 5 after total knee arthroplasty (TKA), and 3 after surgical treatment of hip fracture. Protein supplementation showed beneficial effects across all types of surgery. The primary benefit was a decrease in muscle atrophy compared to placebo as measured by muscle cross sectional area. Multiple authors also demonstrated improved functional measures and quicker achievement of rehabilitation benchmarks. Protein supplementation has beneficial effects on mitigating muscle atrophy in the postoperative period following ACLR, THA, TKA, and surgical treatment of hip fracture. These effects often correlate with improved functional measures and quicker achievement of rehabilitation benchmarks. Further research is needed to evaluate long-term effects of protein supplementation and to establish standardized population-specific regimens that maximize treatment efficacy in the postoperative period.

Anterior cruciate ligament repair versus reconstruction: A clinical, MRI and patient-reported outcome comparison

BACKGROUND

There has been a resurgence in anterior cruciate ligament (ACL) repair for proximal tears using modern surgical techniques and technology. This study aims to compare ACL repair with reconstruction using MRI, clinician-measured and patient-reported outcome measures (PROMs).

METHODS

A post-hoc analysis was performed on prospectively collected data from 20 consecutive primary ACL repairs by the senior author. This was compared with an age and sex-matched cohort of 20 ACL reconstructions by the same surgeon using PROMs, return-to-sport (RTS) testing, and MRI signal noise quotient (SNQ).

RESULTS

Repairs demonstrated equivalent post-operative PROMs to reconstructions as measured by International Knee Documentation Committee subjective score (78.5 ± 17.1 vs. 83.7 ± 13.3, P = 0.333), Tegner Activity Scale (5.9 ± 1.8 vs. 6.1 ± 2.6, P = 0.646) and Lysholm score (89.8 ± 10.0 vs. 89.6 ± 10.4, P = 0.762). There was no difference in repairs and reconstructions passing quadriceps strength criteria (50% vs. 53%, P = 0.097). A greater proportion of repairs passed hamstrings strength criteria (86% vs. 60%, P = 0.023) and hamstrings-to-quadriceps ratio (71% vs. 20%, P = 0.003). There were no differences across hop and Y-balance testing. Repairs had earlier RTS assessment (8.2 ± 2.8 months vs. 10.6 ± 1.4 months, P = 0.020). On 12-month MRI, repairs demonstrated higher femoral (8.8 ± 5.7 vs. 4.6 ± 2.9, P = 0.009) and tibial SNQ (10.0 ± 5.7 vs. 4.3 ± 4.2, P = 0.001), with no mid-substance difference (12.3 ± 8.5 vs. 7.6 ± 5.2, P = 0.074). There were no graft failures.

CONCLUSIONS

When patient selection is optimized for proximal tears, ACL repairs demonstrate equivalent PROMs and better objective outcomes to reconstructions at an earlier timepoint. Repair tissue quality on MRI shows higher signal at tibial and femoral attachments.

Satisfactory Outcomes and Improved Range of Motion With Arthroscopic Lysis of Adhesions and Manipulation for Arthrofibrosis After Multiligamentous Knee Reconstruction

Purpose

To (1) evaluate the efficacy of surgery for arthrofibrosis (AF), as measured by preoperative and postoperative range of motion (ROM), and (2) evaluate patient-reported outcomes at mid- to long-term follow-up.

Methods

We performed a retrospective review of a prospectively collected database including patients who sustained multiligamentous knee injuries (MLKIs) managed surgically, sustained loss of ROM after surgical intervention, and underwent subsequent lysis of adhesions (LOA) and/or manipulation under anesthesia (MUA). Loss of ROM was defined as clinically symptomatic loss of terminal extension (flexion deformity) and/or flexion compared with the contralateral side.

Results

In total, 12 patients (6 male and 6 female patients; age, 36.0 ± 8.7 years; body mass index, 36.3 ± 8.7) met the inclusion criteria and underwent LOA and/or MUA at a mean of 14 ± 27 months (median, 4.0 months; interquartile range, 3.5-9.3 months) after MLKI surgery. Prior to AF intervention, patients showed mean flexion of 75.9° ± 36.0° (range, 30°-129°), mean extension of 3.2° ± 5.2° (range, 0°-12°), and a mean arc of motion of 72.7° ± 34.1° (range, 30°-117°). At a mean follow-up of 7.0 ± 3.9 years (range, 2.4-16.6 years) after AF intervention, patients showed a significant increase in knee flexion of 49° (P = .003), a significant increase in arc of motion of 51° (P = .002), and an increase in extension of 3° (P = .086). The mean final International Knee Documentation Committee score was 59.5 ± 23.9; Lysholm score, 72.1 ± 20.6; Tegner activity scale score, 5.6 ± 2.8; visual analog scale score at rest, 1.0 ± 1.6; and visual analog scale score with use, 3.3 ± 2.5. At final follow-up, 2 patients (17%) had undergone conversion to total knee arthroplasty (TKA) at 10.3 and 24.8 years after MLKI surgery. Of the 10 patients who did not go on to TKA, 9 (90%) reported that they were satisfied or very satisfied with their AF knee surgery.

Conclusions

At mid-term follow-up, LOA and/or MUA for symptomatic AF after multiligamentous knee surgery results in high rates of patient satisfaction and improved knee ROM and pain scores, as well as durable and satisfactory functional outcomes in patients not undergoing TKA.

Level of Evidence

Level IV, therapeutic case series.

Arthroscopic Lysis of Adhesions for Arthrofibrosis After Anterior Cruciate Ligament Reconstruction

BACKGROUND

Arthrofibrosis (AF) after anterior cruciate ligament reconstruction (ACLR) remains a challenge. There is a paucity of data on arthroscopic interventions for AF after ACLR.

PURPOSE

To (1) describe the patient, injury, and surgical characteristics and patient-reported outcomes (PROs) of those requiring an arthroscopic intervention for loss of motion after ACLR and (2) compare outcomes between patients undergoing an early intervention (within 3 months) versus those undergoing a late intervention (after 3 months).

STUDY DESIGN

Case series; Level of evidence, 4.

METHODS

Patients with a history of ACLR and a subsequent operative procedure for postoperative AF at a single institution between 2000 and 2018 were retrospectively identified. Arthroscopic interventions included lysis of adhesions, capsular release with or without manipulation under anesthesia, and excision of cyclops lesions. Patients were excluded if they had a knee dislocation or multiple-ligament injury, a periarticular fracture, or less than 2-year follow-up from the arthroscopic intervention. PROs including the Tegner activity score, visual analog scale pain score, and International Knee Documentation Committee score as well as knee range of motion (ROM) were recorded.

RESULTS

A total of 40 patients were included with a mean age of 27.2 years (range, 11.0-63.8 years) at surgery and a mean follow-up of 10.0 years (range, 2.9-20.7 years). The mean preoperative flexion and extension were 102° (range, 40°-150°) and 8° (range, 0°-25°), respectively. The mean postoperative flexion and extension were 131° (range, 110° to 150°) and 0° (range, -10° to 5°), respectively. After the arthroscopic intervention, the mean ROM improved from 94° (range, 40°-140°) preoperatively to 131° (range, 107°-152°) at final follow-up (P < .001), and the visual analog scale pain score improved from 3.0 preoperatively to 1.2 postoperatively (P = .001). Overall, 13 patients (32.5%) underwent an intervention within 3 months and 27 (67.5%) after 3 months. The early intervention group had a higher postoperative International Knee Documentation Committee score compared with the late intervention group (86.8 vs 71.7, respectively; P = .035).

CONCLUSION

An arthroscopic intervention for AF after ACLR successfully improved knee ROM and pain. Patients who underwent either early or late surgery obtained satisfactory motion and function, although improved PROs were observed when the intervention occurred within 3 months of the primary procedure.

Sex-based differences and relationship with the restricted knee flexion angle due to aging: a comparative study

BACKGROUND

The relationship between inferior patellar mobility (IPM) and knee flexion angle has yet to be elucidated. This study aimed to develop quantitative IPM measurement methods and clarify the relationship between IPM and knee flexion angle in community-dwelling older females.

METHODS

This was a cross-sectional study. Overall, 128 healthy older women (age 65-79 years) were recruited from the community to evaluate the relationship between IPM and knee flexion angle. This study was performed between May 2015 and December 2017. The reference value of and sex differences in IPM were evaluated in 205 healthy young adults aged between 19 and 21 years. IPM was compared between healthy older and young women and was objectively measured using our specially designed patellofemoral arthrometer (PFA). Patellar mobility was calculated by normalization to body height. IPM reliability was assessed before all measurements.

RESULTS

Intraclass correlation coefficients for intratester and intertester reliabilities varied from 0.87 to 0.99. The normal range based on two standard deviations of inferior patellar displacement/body height was 5.9-13.5% (young men), 5.1-14.3% (young women), and 1.2-8.8% (older women). IPM was significantly lower in older than young women (P < 0.001). There was a significant positive correlation (r = 0.72 and P < 0.01) between IPM and knee flexion angle in healthy older women unable to flex the knee joint fully.

CONCLUSIONS

Our PFA has good intratester and intertester reliability. The results suggest that IPM decreases with aging in women. IPM and knee flexion angle are correlated among older women unable to flex the knee joint fully.

CLINICAL TRIAL REGISTRATION

Not applicable.

The combined effects of treadmill exercise and steroid administration on anterior cruciate ligament reconstruction-induced joint contracture and muscle atrophy in rats

Rehabilitation protocols to treat joint contracture and muscle atrophy following anterior cruciate ligament (ACL) reconstruction have not been established. In this study, we examined the combined effects of exercise therapy and steroid administration on joint contracture and muscle atrophy following ACL reconstruction. Rats received ACL transection and reconstructive surgery in one knee. After surgery, they were divided into four groups: no intervention, treadmill exercise (started from day three post-surgery, 12 m/min, 60 min/d, 6 d/week), treatment with the steroidal drug dexamethasone (250 μg/kg on days 0-5, 7, and 9 post-surgery), and dexamethasone treatment plus treadmill exercise. Age-matched untreated rats were used as controls. At day 10 or 30 post-surgery, we assessed ACL-reconstruction-induced joint contracture, joint capsule fibrosis, osteophyte formation, and muscle atrophy of the rectus femoris and gastrocnemius. Treadmill exercise after ACL reconstruction improved several indicators of muscle atrophy in both muscles, but it did not have positive effects on joint contracture. Dexamethasone treatment after ACL reconstruction improved joint contracture and joint capsule fibrosis at both timepoints and partially attenuated osteophyte formation at day 10 post-surgery, but delayed recovery from atrophy of the rectus femoris at day 30 post-surgery. The two treatments combined improved both joint contracture and atrophy of the rectus femoris and gastrocnemius. Exercise therapy combined with steroid administration may therefore be a novel therapeutic strategy for joint contracture and muscle atrophy following ACL reconstruction.

The effects of immobilization duration on joint contracture formation after anterior cruciate ligament reconstruction in rats

BACKGROUND

Both myogenic and arthrogenic factors contribute to contracture formation after anterior cruciate ligament reconstruction surgery. However, effects of immobilization duration on myogenic and arthrogenic contractures after surgery are unknown. We examined the effects of immobilization duration on contracture formation.

METHODS

Rats were divided into groups according to treatment received: untreated control, knee immobilization, anterior cruciate ligament reconstruction, and anterior cruciate ligament reconstruction plus immobilization. Extension range of motion before and after myotomy as well as histomorphological knee changes were assessed two or four weeks after experiment commencement. Range of motion before myotomy mainly represents contractures due to myogenic factors. Range of motion after myotomy represents arthrogenic factors.

FINDINGS

Range of motion before and after myotomy was decreased in the immobilization, reconstruction, and reconstruction plus immobilization groups at both timepoints. In the reconstruction plus immobilization group, range of motion before and after myotomy was significantly smaller than in the immobilization and reconstruction groups. Shortening and thickening of the posterior joint capsule was induced in the immobilization and reconstruction groups. In the reconstruction plus immobilization group, capsule shortening was facilitated via adhesion formation, as compared to the immobilization and reconstruction groups.

INTERPRETATION

Our results indicate that immobilization after anterior cruciate ligament reconstruction surgery facilitates contracture formation via exacerbation of both myogenic and arthrogenic contractures within two weeks. Capsule shortening would be one of the main mechanisms for severe arthrogenic contracture observed in the reconstruction plus immobilization group. Periods of joint immobilization after surgery should be minimized to reduce contracture.

Integration of Task-Based Exoskeleton with an Assist-as-Needed Algorithm for Patient-Centered Elbow Rehabilitation

This research presents an Assist-as-Needed (AAN) Algorithm for controlling a bio-inspired exoskeleton, specifically designed to aid in elbow-rehabilitation exercises. The algorithm is based on a Force Sensitive Resistor (FSR) Sensor and utilizes machine-learning algorithms that are personalized to each patient, allowing them to complete the exercise by themselves whenever possible. The system was tested on five participants, including four with Spinal Cord Injury and one with Duchenne Muscular Dystrophy, with an accuracy of 91.22%. In addition to monitoring the elbow range of motion, the system uses Electromyography signals from the biceps to provide patients with real-time feedback on their progress, which can serve as a motivator to complete the therapy sessions. The study has two main contributions: (1) providing patients with real-time, visual feedback on their progress by combining range of motion and FSR data to quantify disability levels, and (2) developing an assist-as-needed algorithm for rehabilitative support of robotic/exoskeleton devices.

Arthrofibrosis is a common but poorly defined complication in multiligament knee injuries: a systematic review

PURPOSE

The purpose of this study is to systematically review multiligament knee injury (MLKI) outcome studies to determine definitions of arthrofibrosis (AF) and provide information about incidence, management as well as potential risk factors.

METHODS

A systematic literature search was performed (PubMed and Cochrane library) following the PRISMA guidelines of operatively treated MLKI (Schenck II-IV) studies reporting the incidence of AF. Twenty-five studies met the inclusion criteria. Injury pattern, timing of surgery, surgical technique, treatment of AF, rehabilitation programs and PROMS were inquired. Risk of bias and quality of evidence were assessed using the Coleman methodological score.

RESULTS

Twenty-five studies with a total of 709 patients with a mean age of 33.6 ± 4.8 years were included and followed 47.2 ± 32.0 months. The majority of studies (22/25) used imprecise and subjective definitions of AF. A total of 86 patients were treated for AF, resulting in an overall prevalence of 12.1% (range 2.8-57.1). Higher-grade injuries (Schenck III-IV), acute treatment and ROM (range of motion) limiting rehabilitation programs were potential risk factors for AF. The time from index surgery to manipulation anesthesia (MUA) and arthroscopic lysis of adhesions (LOA) averaged at 14.3 ± 8.8 and 27.7 ± 12.8 weeks. Prior to MUA and LOA, the ROM was 51.7° ± 23.5 and 80.2° ± 17.0, resulting in a total ROM gain after intervention of 65.0° ± 19.7 and 48.0° ± 10.6, respectively; with no reports of any complication within the follow-up. The overall methodological quality of the studies was poor as measured by the Coleman score with average 56.3 ± 12.5 (range 31-84) points.

CONCLUSIONS

AF is a common but poorly defined complication particularly in high-grade MLKI. Early postoperative and intensified physiotherapy is important to reduce the risk of AF. MUA and LOA are very effective treatment options and result in good clinical outcome. Prospective studies with bigger study population are needed to optimize treatment algorithms of further patients after MLKI. The protocol of this systematic review has been prospectively registered with PROSPERO (CRD42021229187, January 4th, 2021).

Efficacy of Repair for ACL Injury: A Meta‑analysis of Randomized Controlled Trials

We aim to compare the curative effect of primary repair for anterior cruciate ligament (ACL) injury with reconstruction and provide the reliable evidence for its clinical application. The literatures were searched in PubMed, EMBASE, Springer, and other medical literature databases published between January 1970 and June 2021. Basic characteristics, surgery technique, clinical outcome scores and physical examination results were recorded and evaluated. Seven randomized controlled trials (RCT) were eligible for inclusion. The results showed that there were no statistically significant differences between arthroscopic ACL repair and ACL reconstruction for Tegner, Lysholm, Lachman, KT-1000, range of motion (ROM), functional outcomes and reoperation rate (P>0.05), even the result of IKDC scores showed that arthroscopic repair was better than reconstruction (P=0.04). However, through the subgroup analysis, it was found that the short-term follow-up results of arthroscopic ACL repair were indeed better than those of open ACL repair. Therefore, we can assume that the arthroscopic ACL repair technique is an optional and promising surgical method to treat ACL injury.

Low-level laser therapy attenuates arthrogenic contracture induced by anterior cruciate ligament reconstruction surgery in rats

Therapeutic approaches to treat joint contracture after anterior cruciate ligament (ACL) reconstruction have not been established. Arthrofibrosis accompanied by joint inflammation following ACL reconstruction is a major cause of arthrogenic contracture. In this study, we examined whether anti-inflammatory treatment using low-level laser therapy (LLLT) can prevent ACL reconstruction-induced arthrogenic contracture. Rats underwent ACL transection and reconstruction surgery in their right knees. Unoperated left knees were used as controls. After surgery, rats were reared with or without daily LLLT (wavelength: 830 nm; power output: 150 mW; power density: 5 W/cm2; for 120 s/day). We assessed the passive extension range of motion (ROM) after myotomy at one and two weeks post-surgery; the reduction in ROM represents the severity of arthrogenic contracture. ROM was markedly decreased by ACL reconstruction at both time points; however, LLLT partially attenuated the decrease in ROM. One week after ACL reconstruction, the gene expression of the proinflammatory cytokine interleukin-1beta in the joint capsule was significantly upregulated, and this upregulation was significantly attenuated by LLLT. Fibrotic changes in the joint capsule, including upregulation of collagen type I and III genes, shortening of the synovium, and thickening were caused by ACL reconstruction and seen at both time points. LLLT attenuated these fibrotic changes as well. Our results indicate that LLLT after ACL reconstruction could attenuate the formation of arthrogenic contracture through inhibition of inflammation and fibrosis in the joint capsule. Thus, LLLT may become a novel therapeutic approach for ACL reconstruction-induced joint contracture.

Arthroscopic Anterior Cruciate Ligament Repair Versus Autograft Anterior Cruciate Ligament Reconstruction: A Meta-Analysis of Comparative Studies

Purpose

To compare the clinical outcomes of arthroscopic anterior cruciate ligament (ACL) repair and autograft ACL reconstruction for ACL ruptures.

Methods

PubMed, EMBASE, Scopus, Web of Science and The Cochrane Library were searched for relevant studies from 1 January 1990 to 21 March 2022. Two evaluators independently screened the literature, extracted data and assessed the methodological quality of the enrolled studies. Meta-analysis was conducted using RevMan 5.4 software.

Results

Ten studies with mean follow-up periods from 12 to 36 months were included. For 638 patients with ACL ruptures, arthroscopic ACL repair showed statistically comparable outcomes of failure (p = 0.18), complications (p = 0.29), reoperation other than revision (p = 0.78), Lysholm score (p = 0.78), Tegner score (p = 0.70), and satisfaction (p = 0.45) when compared with autograft ACL reconstruction. A significantly higher rate of hardware removal (p = 0.0008) but greater International Knee Documentation Committee (IKDC) score (p = 0.009) were found in the ACL repair group. The heterogeneity of the side-to-side difference of anterior tibial translation (ΔATT) was high (I 2 = 80%). After the sensitivity analysis, the I 2 decreased dramatically (I 2 = 32%), and the knees with ACL repair showed significantly greater ΔATT (P = 0.04).

Conclusion

For proximal ACL ruptures, arthroscopic ACL repair showed similar clinical outcomes, and even better functional performance when compared to autograft ACL reconstruction. ACL repair has a higher rate of hardware removal, and might be related to greater asymptomatic knee laxity. More high-quality prospective trials are needed to confirm our findings.

Does Flipping the Tubercle for Improved Cartilage Repair Exposure Increase the Risk for Arthrofibrosis?

OBJECTIVE

We sought to determine whether rates of postoperative arthrofibrosis following tibial tuberosity osteotomy (TTO) with complete mobilization of the fragment (TTO-HD) are comparable to TTOs where the hinge remained intact (TTO-HI).

DESIGN

Patients who underwent TTO with concomitant cartilage repair procedure between January 2007 and May 2017, with at least 2 years of follow-up were included in this study. Postoperative reinterventions following TTO-HD and TTO-HI were assessed and multivariant logistic regression models were used to identify whether postoperative reinterventions can be attributed to either technique when controlled for defect size or defect number.

RESULTS

A total of 127 patients (TTO-HD, n = 80; TTO-HI, n = 47) were included in this study. Significantly more patients in the TTO-HD group (31.2%) developed postoperative arthrofibrosis compared with TTO-HI (6.4%; P < 0.05). Multivariant logistic regression revealed that TTO-HD is an independent risk factor for predicting postoperative arthrofibrosis (OR 6.5, CI = 1.7-24.2, P < 0.05).

CONCLUSION

Patients who underwent TTO with distal hinge detachment and a proximally flipped tubercle for better exposure during concomitant cartilage repair were at a significantly higher risk of postoperative arthrofibrosis than patients with similar size and number of defects treated without mobilization of the tubercle. While certain procedures can benefit from larger exposure, surgeons should be aware of the increased risk of postoperative arthrofibrosis.

LEVEL OF EVIDENCE

Level III, case-control study.

Effects of Each Phase of Anterior Cruciate Ligament Reconstruction Surgery on Joint Contracture in Rats

BACKGROUND

Although anterior cruciate ligament reconstruction surgery is known to cause joint contracture, the mechanisms of this process are unknown. We aimed to assess the effects of transection of this ligament and each phase of reconstruction surgery on contracture formation.

MATERIALS AND METHODS

Rats were divided into groups according to treatment received: sham (arthrotomy), ligament transection, ligament transection plus bone drilling, and ligament reconstruction. Surgery was performed on the right knee. Untreated left knees in the sham group were used as controls.

RESULTS

At 7 and 28 d post-surgery, range of motion before myotomy, mainly representing myogenic contracture, was restricted in the sham and ligament transection groups, and more so in the bone drilling and reconstruction groups. Restricted range of motion after myotomy, representing arthrogenic contracture, was detected at both timepoints in the bone drilling and reconstruction groups, but not in the sham or ligament transection groups. At 3 d post-surgery, although a large blood clot was observed in all three treatment groups, only the bone drilling and reconstruction groups showed significant joint swelling. At 7 d post-surgery, inflammatory-cell infiltration into the joint capsule was most apparent in the bone drilling and reconstruction groups, and joint capsule fibrosis was also most apparent in these groups at 7 and 28 d post-surgery.

CONCLUSIONS

Our results suggest that (1) myogenic contracture after anterior cruciate ligament reconstruction is caused by arthrotomy and aggravated by bone drilling, and (2) arthrogenic contracture is mostly due to bone drilling, which triggers an inflammation-fibrosis cascade.

A rat model of arthrofibrosis developed after anterior cruciate ligament reconstruction without rigid joint immobilization

Purpose: Complications including arthrofibrosis have been reported after anterior cruciate ligament reconstruction (ACLR) even under accelerated rehabilitation. To overcome this, we developed an animal model of ACLR-induced arthrofibrosis without immobilization.Materials and Methods: Thirteen male Wistar rats were divided into ACL transection (ACLT) and ACLR groups. Surgery was performed in the right knees and untreated left knees were used as controls. After surgery, rats could move freely without joint immobilization.Results: One week after surgery, flexion contracture represented by passive ROM reduction was 49 ± 5° and 21 ± 6° in ACLR and ACLT groups, respectively. Thereafter, flexion contractures were gradually reduced to 21 ± 8° and 12 ± 6° after 12 weeks, respectively. Fibrosis, which is characterized by significant upregulation of fibrosis-related genes, thickening, and adhesion in the posterior joint capsule, was observed in the ACLR group after 12 weeks of surgery. Nociceptive behavior and joint swelling were more apparent in the ACLR group than in the ACLT group, especially after 1 week of surgery.Discussions: We developed a rat model of ACLR-induced joint contracture due to arthrofibrosis without rigid immobilization. Joint contracture was also observed in the ACLT group, but to a considerably milder degree than in the ACLR group. Thus, signs of inflammation as a result of reconstruction surgery, rather than ACL transection, play an important role in the formation of joint contracture after ACLR. Our animal model is suited to examine the mechanisms and efficacy of therapeutic strategies for arthrofibrosis following ACLR treated without rigid joint immobilization.

Formation process of joint contracture after anterior cruciate ligament reconstruction in rats

Knee joint contracture is often induced by anterior cruciate ligament reconstruction (ACLR). However, the temporal and spatial arthrofibrotic changes following inflammatory events, which occur in parallel with the formation of joint contractures after ACLR, are unknown. This study aimed to reveal: (a) time-dependent changes in myogenic and arthrogenic contractures; and (b) the process of arthrofibrosis development after ACLR. ACLR was performed on knees of rats unilaterally. Passive ranges of motions (ROMs) before and after myotomy, as well as inflammatory and fibrotic reactions, were examined before and after the surgery at various periods up to 56 days. Both ROMs before and after myotomy exhibited their lowest value on day 7 and increased thereafter in a time-dependent manner; nevertheless, significant restrictions remained by day 56. Myotomy partially increased ROMs at all time points, indicating contribution of the myogenic component to ACLR-induced contracture. Inflammatory and fibrotic reactions peaked on day 7. Arthrofibrosis, characterized by the thickening of the joint capsule and the shortening of the synovial length, was established by day 7 and was not completely resolved by day 56. Our results indicate that: (a) both myogenic and arthrogenic contractures generated through ACLR develop maximally by day 7 after surgery and subside thereafter, but persist at least until day 56; and (b) arthrofibrosis is established by day 7 after surgery and is not completely resolved by day 56. These findings suggest that treatment and intervention for preventing joint contracture after ACLR should be performed within the first 7 days after surgery.

Anterior cruciate ligament femoral-tunnel drilling through an anteromedial portal: 3-dimensional plane drilling angle affects tunnel length relative to notchplasty

Background

Notchplasty is a surgical technique often performed during anterior cruciate ligament reconstruction (ACLR) with widening of the intercondylar notch of the lateral distal femur to avoid graft impingement. The purpose of this study was to correlate femoral-tunnel length with 3-dimensional (3D) drilling angle through the anteromedial (AM) portal with and without notchplasty.

Materials and methods

Computer data were collected from an anatomical study using 16 cadaveric knees. The anterior cruciate ligament (ACL) femoral insertion was dissected and outlined for gross anatomical observation. The dissected cadaveric knees were scanned by computed tomography (CT). Three-dimensional measurements were calculated using software (Geomagic, Inc., Research Triangle Park, NC, USA) and included the center of the ACL footprint and the size of the ACL femoral footprint. The femoral-tunnel aperture centers were measured in the anatomical posterior-to-anterior and proximal-to-distal directions using Bernard’s quadrant method. The ACL tunnel was created 3-demensionally in the anatomical center of femoral foot print of ACL using software (SolidWorks®, Corp., Waltham, MA, USA). The 8-mm cylinder shaped ACL tunnel was rested upon the anatomical center of the ACL footprint and placed in three different positions: the coronal plane, the sagittal plane, and the axial plane. Finally, the effect of notchplasty on the femoral-tunnel length and center of the ACL footprint were measured. All the above-mentioned studies performed ACLR using the AM portal.

Results

The length of the femoral tunnels produced using the low coronal and high axial angles with 5-mm notchplasty became significantly shorter as the femoral starting position became more horizontal. The result was 30.38 ± 2.11 mm on average at 20° in the coronal plane/70° in the axial plane/45° in the sagittal plane and 31.26 ± 2.08 mm at 30° in the coronal plane/60° in the axial plane/45° in the sagittal plane, respectively, comparing the standard technique of 45° in the coronal/45° in the axial/45° in the sagittal plane of 32.98 ± 3.04 mm (P < 0.001). The tunnels made using the high coronal and low axial angles with notchplasty became longer than those made using the standard technique: 40.31 ± 3.36 mm at 60° in the coronal plane/30° in the axial plane/45° in the sagittal plane and 50.46 ± 3.13 mm at 75° in the coronal plane/15° in the axial plane/45° in the sagittal plane (P < 0.001).

Conclusions

Our results show that excessive notchplasty causes the femoral tunnel to be located in the non-anatomical center of the ACL footprint and reduces the femoral-tunnel length. Therefore, care should be taken to avoid excessive notchplasty when performing this operation.

Standard MRI May Not Predict Specific Acute Anterior Cruciate Ligament Rupture Characteristics

Background

There has been renewed interest in the concept of anterior cruciate ligament (ACL) suture repair (ACLSR). Morphologic characteristics of the ruptured ACL remnant play a role in deciding whether a patient is eligible for ACLSR. However, no classification of these characteristics of ACL rupture on magnetic resonance imaging (MRI) scans has yet been compared with intraoperative findings in the context of ACLSR.

Purpose

To investigate the value of using preoperative MRI to predict specific characteristics of acute complete ACL rupture.

Study Design

Cohort study (diagnostic); Level of evidence, 2.

Methods

A total of 25 patients were included. Two radiologists classified ACL rupture location and pattern on preoperative 1.5-T MRI scans with a standard sequence; the results were compared with the corresponding findings at arthroscopy conducted by a single surgeon. The agreement between the MRI and surgical findings was calculated using Cohen κ values. Furthermore, the reliability coefficients of the MRI classifications within and between radiologists were calculated.

Results

The agreement between MRI classification and arthroscopic findings for ACL rupture location was slight (Cohen κ, 0.016 [radiologist 1] and 0.087 [radiologist 2]), and for ACL rupture pattern, this was poor to slight (Cohen κ, <0 and 0.074). The intraobserver reliability of MRI classification for ACL rupture location was moderate for radiologist 1 and slight for radiologist 2 (Cohen κ, 0.526 and 0.061, respectively), and for ACL rupture pattern, this was slight for radiologist 1 and 2 (Cohen κ, 0.051 and 0.093, respectively). The interobserver reliability of MRI classification for ACL rupture location and pattern was slight between radiologists (Cohen κ, 0.172 and 0.040, respectively).

Conclusion

In the current study, we found poor to slight agreement between MRI classification and arthroscopic findings of specific ACL rupture characteristics. In addition, the intra- and interobserver reliability for MRI classification of the ACL rupture characteristics was slight to moderate.

Association Between Femoral "Spike" Size After Intramedullary Nailing and Subsequent Knee Motion Surgery

OBJECTIVES

To determine the association between displaced femoral shaft bone fragments ("spikes") seen on radiographs after intramedullary nail insertion and the need for future motion surgery.

DESIGN

Retrospective case-control study.

SETTING

Academic trauma center.

PATIENTS

We included patients with femoral shaft fractures treated with intramedullary nail insertion. Case patients (n = 22) had developed knee stiffness treated with motion surgery. The control group was a randomly selected sample (1:3 ratio).

MAIN OUTCOME MEASURES

Motion surgery to address knee stiffness. We defined a "spike distance ratio" and "spike area ratio" from initial postoperative anteroposterior and lateral radiographs. Multivariable logistic regression determined the effect of spike distance and area ratios on the likelihood of need for motion surgery, controlling for polytraumatic injuries and bilateral fractures.

RESULTS

The case group had a median femoral spike distance ratio of 1.9 [interquartile range (IQR), 1.6-2.5] compared with 1.5 (IQR, 1.2-1.8) in the control group. An increased femoral spike distance ratio was associated with increased odds of motion surgery (P < 0.01). A femoral spike distance >2 times the femoral radius had 32 times the odds (95% confidence interval, 2-752) of motion surgery compared with patients with distance ratios <1.25. Median femoral spike area ratios were similar between the case (0.2; IQR, 0.1-0.5) and control (0.2; IQR, 0.0-0.5) groups and were not associated with increased odds of motion surgery (P = 0.34).

CONCLUSIONS

A larger spike distance ratio is associated with increased odds of subsequent motion surgery.

LEVEL OF EVIDENCE

Prognostic Level III. See Instructions for Authors for a complete description of levels of evidence.

Principles of Rehabilitation

Developing and implementing a rehabilitation program is one of the most challenging patient care skills because it requires a firm grasp of the healing process and available treatment options, which must then be serially compared with the pathologic condition of the injury and the patient's progress. This cyclical problem-based approach to rehabilitation allows clinicians to most effectively individualize the rehabilitation plan to the patient's individual needs and progress. In each phase of the rehabilitation process, problems should be identified and goals developed taking into consideration the phase of healing.

Notchplasty alters knee biomechanics after anatomic ACL reconstruction

PURPOSE

The aims of this study were (1) to study the biomechanics of single-bundle anatomic ACL reconstructed knees with and without notchplasty using a robotic testing system and (2) to determine if there would be a difference between performing a small or large notchplasty.

METHODS

Fifteen fresh-frozen specimens were used in this study. The ACL reconstruction (ACL-R) was performed using an anatomic single-bundle technique with the 8 mm soft tissue graft fixed at 30° with suspensory fixation on the femoral side and a screw and washer on the tibial side. The notchplasty was then created with a burr. The following knee states were compared: (1) ACL-R, (2) ACL-R with a small (3 mm) notchplasty, and (3) ACL-R with a large (6 mm) notchplasty. Four loading conditions were applied: (1) an anterior drawer with an 89 N anterior tibial load, (2) simulated pivot-shift loading, (3) a 5 Nm internal rotational moment, and (4) a 5 Nm external rotational moment.

RESULTS

Under anterior tibial loading, anterior tibial translation increased, and graft force decreased significantly after ACL-R + 3 mm notchplasty and ACLR + 6 mm notchplasty compared to ACL-R alone at FE, 15° and 30° of knee flexion. There were no changes in either anterior tibial translation or graft force under simulated pivot-shift loading, internal rotational moment, or external rotational moment.

CONCLUSION

When added to anatomic ACL reconstruction, notchplasty increased anterior tibial translation and decreased graft forces during low knee flexion angles. There was no difference between a small and large notchplasty. The findings of this study are clinically relevant as the purpose of anatomic ACL reconstruction is to restore normal knee laxity, and while notchplasty may be helpful in avoiding graft impingement and improving visualization, removing even 3 mm of bone leads to biomechanical changes.

Postoperative Magnetic Resonance Imaging following Arthroscopic Primary Anterior Cruciate Ligament Repair

Introduction

Recently, there has been a resurgence of interest in arthroscopic primary anterior cruciate ligament (ACL) repair. To date, no studies have assessed the role of postoperative magnetic resonance imaging (MRI) on the status and maturation of the repaired ligament. The goal of this study was therefore to assess (I) the accuracy of MRI on rerupture of the repaired ligament and (II) the maturation of the repaired ACL.

Methods

All postoperative MRIs of patients that underwent arthroscopic primary ACL repair were included. A musculoskeletal radiologist, blinded for MRI indication, surgery-MRI time interval, and clinical stability, retrospectively assessed the ligament continuity and graded ligament maturation as hypointense (similar to intact PCL), isointense (>50% similar to PCL), or hyperintense (<50% similar to PCL).

Results

Thirty-seven MRIs were included from 36 patients. Mean age was 30 years (range: 14–57 years), and mean surgery-MRI interval was 1.5 years (range: 0.1–4.9 years). The radiologist recognized 6 out of 8 reruptures and 26 out of 29 intact ligaments (sensitivity 75%, specificity 90%, and accuracy 86%). Ligaments in the first year were more often hyperintense than after one year (60% vs. 11%, p=0.02), most often isointense (60%) between one and two years, and more often hypointense after two years than before two years (56% vs. 10%, p=0.03).

Conclusion

Postoperative MRI was found to accurately predict the rerupture of the primarily repaired ACL. Furthermore, it can be expected that the repaired ligament is hyperintense within the first year, while the signal becomes similar to the intact PCL after two years.

Self-reported functional recovery after reconstruction versus repair in acute anterior cruciate ligament rupture (ROTOR): a randomized controlled clinical trial

BACKGROUND

Anterior cruciate ligament (ACL) reconstruction is today's surgical gold standard for ACL rupture. Although it provides satisfactory results, not all patients return to their previous activity level and moreover, early posttraumatic osteoarthritis is not prevented. As such, a renewed interest has emerged in ACL suture repair combined with dynamic augmentation. Compared to ACL reconstruction, the hypothesized advantages of ACL suture repair are earlier return to sports, reduction of early posttraumatic osteoarthritis and preservation of the patient's native ACL tissue and proprioceptive envelope of the knee. In recent literature, ACL suture repair combined with dynamic augmentation tends to be at least equally effective compared to ACL reconstruction, but no randomized comparative study has yet been conducted.

METHODS/DESIGN

This study is a prospective, stratified, block randomized controlled trial. Forty-eight patients with an ACL rupture will be assigned to either a suture repair group with dynamic augmentation and microfracture of the femoral notch, or an ACL reconstruction group with autologous semitendinosis graft and all-inside technique. The primary objective is to investigate the hypothesis that suture repair of a ruptured ACL results in at least equal effectiveness compared with an ACL reconstruction in terms of patient self-reported outcomes (IKDC 2000 subjective scale) 1 year postoperatively. Secondary objectives are to evaluate patient self-reported outcomes (IKDC 2000, KOOS, Tegner, VAS), re-rupture rate, rehabilitation time required for return to daily and sports activities, achieved levels of sports activity, clinimetrics (Rolimeter, LSI, Isoforce) and development of osteoarthritis, at short term (6 weeks, 3, 6 and 9 months and 1 year), midterm (2 and 5 years) and long term (10 years) postoperatively.

DISCUSSION

A renewed interest has emerged in ACL suture repair combined with dynamic augmentation in the treatment of ACL rupture. Recent cohort studies show good short- and midterm results for this technique. This randomized controlled trial has been designed to compare the outcome of suture repair of a ruptured ACL, combined with DIS as well as microfracture of the femoral notch, with ACL reconstruction using autologous semitendinosus.

TRIAL REGISTRATION

Clinical Trials Register NCT02310854 (retrospectively registered on December 1st, 2014).

Clinical Outcomes of Arthroscopic Primary Repair of Proximal Anterior Cruciate Ligament Tears Are Maintained at Mid-term Follow-up

PURPOSE

To assess the mid-term clinical outcomes in patients with proximal avulsion anterior cruciate ligament (ACL) tears undergoing arthroscopic primary repair with suture anchors.

METHODS

The first 11 consecutive patients with proximal avulsion tears treated with arthroscopic primary repair were evaluated at mid-term (minimum 5-year) follow-up. Physical examination was performed; laxity examination consisting of the Lachman, pivot-shift, and anterior drawer tests was performed; and patients were asked to complete the Lysholm, modified Cincinnati, Single Assessment Numeric Evaluation, and International Knee Documentation Committee (IKDC) questionnaires.

RESULTS

Of the 11 patients, 10 were seen at a mean follow-up of 6.0 ± 1.5 years (range, 4.8-9.2 years). One patient was lost to follow-up, in whom failure had already occurred at short-term follow-up. One additional patient underwent reoperation for a medial meniscus tear and also had a partial ACL tear; this patient was clinically stable at last follow-up. All patients had full range of motion. Nine patients had negative Lachman and negative pivot-shift examination findings (IKDC score of A), and 1 patient had a 1A Lachman result and 1+ pivot-shift result (IKDC score of B). The mean Lysholm score was 96.0 ± 4.5 (range, 88-100); modified Cincinnati score, 95.6 ± 7.4 (range, 80-100); Single Assessment Numeric Evaluation score, 95.4 ± 5.4 (range, 85-100); preinjury Tegner score, 7.2 ± 1.2 (range, 5-9); postoperative Tegner score, 6.6 ± 1.8 (range, 3-9); and IKDC subjective score, 92.3 ± 11.3 (range, 64-100).

CONCLUSIONS

The clinical outcomes of arthroscopic primary repair of proximal ACL tears with suture anchors are excellent and are maintained at mid-term follow-up in a carefully selected subset of patients with proximal tears and excellent tissue quality.

LEVEL OF EVIDENCE

Level IV, therapeutic case series.

Role of tear location on outcomes of open primary repair of the anterior cruciate ligament: A systematic review of historical studies

BACKGROUND

The general opinion is that outcomes of open primary repair of the anterior cruciate ligament (ACL) in the historical literature were disappointing. Since good outcomes of primary repair of proximal tears have recently been reported, we aimed to assess the role of tear location on open primary repair outcomes in the historical literature.

METHODS

All studies reporting outcomes of open primary ACL repair published between the inception of PubMed, Embase and Cochrane and 2000 were identified. Studies were included if tear location was reported. Outcome scores, return to sports, stability examinations, failures and patient satisfaction were collected and reviewed in the total study cohort and in a subgroup of studies treating only proximal tears. Spearman correlation analysis was performed between the percentage of proximal tears in the studies and all outcomes.

RESULTS

Twenty-nine studies were included reporting outcomes of open primary in 1457 patients of which 72% had proximal and 23% midsubstance tears. Mean age was 30years, 65% were males, and mean follow-up was 3.6years. Good outcomes were noted in the total cohort, and excellent outcomes were noted following repair of proximal tears. Positive correlation was found between the percentage proximal tears in the studies and percentage satisfied patients (p=0.010).

CONCLUSION

Tear location seems to have played a role on the outcomes of open primary ACL repair. Outcomes of open primary repair in patients with proximal tears were excellent, which confirms there may be a potential role for primary repair as treatment for proximal ACL tears.

Range of motion and complications following primary repair versus reconstruction of the anterior cruciate ligament

INTRODUCTION

Recently, there has been a resurgence of interest in primary anterior cruciate ligament (ACL) repair. The procedure is less invasive than ACL reconstruction, yet studies assessing early postoperative course are lacking. Goal therefore was to assess postoperative range of motion (ROM), complications and operative times following primary repair and compare this to the gold standard of reconstruction.

METHODS

A retrospective study was performed for which 52 repair and 90 reconstruction patients could be included. Patients were examined at one week and one, three and six months. Rehabilitation protocol consisted of early ROM and was equal for both groups. Outcomes were compared using independent t-tests and chi-square tests, and reported in mean±standard deviation.

RESULTS

Repair had more ROM than reconstruction patients at one week (89°±18 vs. 61°±21, p<0.01) and one month (125°±14 vs. 116°±18, p < 0.01) postoperatively. Fewer repair patients had 90° ROM at one week (23% vs. 84%, p<0.01), and more repair patients had full ROM at one month (57% vs. 30%, p<0.01). Treatment of meniscal lesions, but not chondral lesions, influenced ROM. Trends towards fewer complications (2% vs. 9%, p=0.19) and infections (0% vs. 6%, p=0.20) were noted following primary repair, and the procedure was significantly shorter.

CONCLUSIONS

Following primary repair, patients had better ROM, and trends towards fewer complications than reconstruction. Primary repair is a safe, brief procedure with early ROM and low complication rates.

Presentation and management of arthrofibrosis of the knee: A case report

STUDY DESIGN

Case report.

BACKGROUND

Arthrofibrosis is a debilitating condition that results in pain, decreased range of motion, and decreased function. Although surgical management of arthrofibrosis has been well described in the literature, rehabilitation of the arthrofibrotic knee is less well described.

CASE DESCRIPTION

A 28-year-old female presented with swelling, pain, and decreased strength, range of motion, patellar mobility, and function following an exploratory arthroscopy of her left knee. After failed conservative management, the patient underwent two additional surgeries to remove scar tissue. Following each surgery, the emphasis was on decreasing inflammation and maintaining patellar mobility while increasing joint range of motion and strength. Therapy progression was determined by the presence or absence of inflammatory signs. The second scar tissue removal surgery resulted in a femoral neuropathy that further complicated the rehabilitation process.

OUTCOMES

At 3-year follow-up, the patient continued to present with decreased range of motion and strength compared to the uninvolved limb, but had returned to a modified running program and reported pain no longer limited her ability to participate in activities of daily living.

DISCUSSION

This case report highlights the importance of recognizing that arthrofibrosis may result following a minor knee surgery and with minimal range of motion loss. Additional complications also may result during arthrofibrosis treatment. Progressing rehabilitation based on the inflammatory response may decrease the likelihood of additional scar tissue formation and potentially improve the outcome for the patient.

Rehabilitation Principles of the Anterior Cruciate Ligament Reconstructed Knee: Twelve Steps for Successful Progression and Return to Play

The rehabilitation process begins immediately after injury to the anterior cruciate ligament (ACL). The goal of preoperative rehabilitation is to prepare the patient for surgery. Current rehabilitation programs focus on strengthening exercises and proprioceptive and neuromuscular control drills to provide a neurologic stimulus. It is also important to address preexisting factors, especially for the female athlete, that may predispose to future injury, such as hip and hamstring weakness. Our goal in the rehabilitation program is to restore full, unrestricted function and to assist the patient to return to 100% of the preinjury level while achieving excellent long-term outcomes.

Gap formation following primary repair of the anterior cruciate ligament: A biomechanical evaluation

BACKGROUND

Historically, inconsistent and unpredictable results of open primary anterior cruciate ligament (ACL) repair were reported. Recently, however, good results of arthroscopic primary ACL repair of proximal tears have been reported. Purpose of this study was to assess the direct postoperative gap formation and maximum failure load following simulated knee motion after primary ACL repair.

METHODS

Six matched-paired human cadaveric knees (mean age: 52years, range: 48 to 56years) were used. After primary proximal ACL repair with either suture button fixation or suture anchor fixation, knees were cycled five, 50 and 100 times with a simulated active quadriceps force. Gap formation between the femoral wall and ligament was measured using a digital caliper and maximum failure load was tested.

RESULTS

Gap formation after five, 50 and 100cycles of the knee were 0.30mm (±0.23), 0.75mm (±0.55) and 0.97mm (±0.70), respectively, with no significant differences between both fixation techniques. The overall maximum failure load was 243N (±143) with no difference between both techniques. Most common failure mode was slipping of suture from the fixation.

CONCLUSION

Following proximal ACL repair, gap formation of approximately one millimeter was measured after repetitious knee cycling with mean maximum failure load of 243N. These findings are likely to be sufficient for careful early active range of motion (ROM) when extrapolating from other available studies. Future studies with second-look arthroscopy are necessary to assess the gap formation and healing in patients treated with primary repair.

Procedural intervention for arthrofibrosis after ACL reconstruction: trends over two decades

PURPOSE

Arthrofibrosis is a rare complication after anterior cruciate ligament (ACL) reconstruction. The purpose of this study was to (1) report a population-based incidence of arthrofibrosis (as defined by manipulation under anaesthesia or surgical lysis of adhesions) following ACL injury and reconstruction, (2) identify risk factors associated with development of arthrofibrosis, and (3) report outcomes of intervention for arthrofibrosis.

METHODS

This was a historical cohort study performed in Olmsted County, Minnesota. The Rochester Epidemiology Project (REP) was used to identify a population-based cohort of individuals with new-onset, isolated ACL tears between 1 January 1990 and 31 December 2010. The REP database provides access to all medical records for each resident of Olmsted County, regardless of the facility where the care was delivered. A total of 1841 individuals were identified with new-onset, isolated ACL tears and were confirmed with chart review. The intervention incidence for arthrofibrosis was then calculated, and various predictive factors including age, sex, calendar year, and meniscal injury were investigated.

RESULTS

During follow-up, 5 patients (1.0 %) in the non-operative cohort and 23 patients (1.7 %) in the ACL reconstruction cohort received intervention for arthrofibrosis, corresponding to an incidence of 0.7 per 1000 person-years in the non-operative cohort and 1.9 per 1000 person-years in the ACL reconstruction cohort. Female patients were 2.5 times more likely to have arthrofibrosis than males. The mean preoperative range of motion was -8° to 83° and improved to a mean of -2° to 127° post-operatively.

CONCLUSIONS

Arthrofibrosis remains a rare but potentially devastating complication after ACL reconstruction, and roughly 2 % of patients had post-operative stiffness that required intervention. Female patients are at higher risk of arthrofibrosis. However, when patients develop severe motion complications after ACL injury, interventions are generally effective in preventing permanent arthrofibrosis.

Postoperative Infection After Anterior Cruciate Ligament Reconstruction

Context:

Infection after anterior cruciate ligament reconstruction (ACLR) is uncommon; if it occurs, it can lead to disastrous complications.

Objective:

To analyze post-ACLR infections and identify related complications to provide the most effective treatment protocol.

Study Design:

Clinical review.

Level of Evidence:

Level 4.

Results:

Among approximately 1850 ACLRs performed by a single surgeon over the past 20 years, 7 cases of post-ACLR infection were identified (incidence, 0.37%). Five patients presenting with low-severity infection were successfully treated without any complication or residual functional disability. The remaining 2 patients, although successfully treated, presented with minor residual limitations. From a literature review, 16 studies including 246 cases of infection were reported among 35,795 ACLRs, making the rate of infection 0.68% (range, 0.14%-2.6%).

Conclusion:

With proper treatment protocols, post-ACLR infection is rare but can compromise outcomes.

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.

Primary repair of the anterior cruciate ligament: A paradigm shift

Over the last century, many surgical treatments have been developed in the orthopedic field, including treatments of anterior cruciate ligament (ACL) injuries. These treatments ideally evolve in a process of trial and error with prospective comparison of new treatments to the current treatment standard. However, these evolutions are sometimes not linear and periodically undergo paradigm shifts. In this article, we review the evolution of ACL treatment and explain how it underwent a paradigm shift. Open primary ACL repair was the most common treatment in the 1970s and 1980s, but because multiple studies noted deterioration of outcomes at mid-term follow-up, in addition to several randomized clinical trials (RCTs) that noted better outcomes following ACL reconstruction, the open primary repair technique was abandoned. At the end of the primary repair era, however, several studies showed that outcomes of open primary repair were good to excellent and did not deteriorate when this technique was selectively performed in patients with proximal ACL tears, whereas primary repair led to disappointing and unpredictable results in patients with mid-substance tears. Unfortunately, enrollment of patients in the aforementioned RCTs was already finished, ultimately leading to abandoning of open primary repair, despite the advantages of ligament preservation. In this review, we discuss (I) why the evolution of ACL treatment underwent a paradigm shift, (II) which factors may have played a role in this and (III) what the future role of arthroscopic primary ACL repair is in the evolution of ACL treatments.

Novel Protocol for Knee Mobilization Under Femoral and Sciatic Nerve Blocks for Postoperative Knee Stiffness

The purpose of this study was to evaluate the effectiveness of intermittent femoral and sciatic nerve blocks combined with an in-house physiotherapy protocol for treating postoperative knee stiffness. Sixty-eight patients with postoperative knee stiffness were evaluated for passive knee flexion and extension at different time points, beginning preoperatively and continuing throughout a median 10-month follow-up after mobilization intervention. Sciatic and femoral nerve catheters were activated 1 hour prior to each physiotherapy session, which was performed twice per day and supported by a continuous passive range of motion machine. Median time from admission to catheter removal was 4 days (range, 1-8 days). Mean hospital length of stay was 7 days (range, 2-19 days). Overall mean flexion increased significantly from pretreatment (74°) to discharge (109°; P<.01). There was no significant difference in mean flexion at 6-week follow-up compared with that at discharge (108°; P=.764), but there was a significant increase in flexion at final follow-up (120°; P=.002). Overall mean knee extension lag decreased significantly from pretreatment (5°) to discharge (0.4°; P=.001). There was no significant increase in mean extension lag from discharge to final follow-up (1°; P=.2). Overall, 11 patients underwent revision surgery for persistent stiffness. This novel protocol for continuous knee mobilization under perineural blocks is a valuable alternative to knee manipulation under anesthesia for this select group of procedures. The 2 techniques produced a similar early range of motion gain, but the reported protocol resulted in less range of motion loss at follow-up and fewer possible complications. [Orthopedics. 2016; 39(4):e708-e714.].

Extension deficit after ACL reconstruction: Is open posterior release a safe and efficient procedure?

BACKGROUND

Extension loss is a potentially devastating consequence of anterior cruciate ligament reconstruction (ACLR). It can often be treated by anterior arthroscopic release. In rare cases, a chronic flexion contracture requires an additional posterior open release. To our knowledge, no study analysing the results of both posteromedial and posterolateral approaches has been performed so far. The purposes of this study were (1) to analyse the midterm outcome and complications of a combined procedure, anterior arthroscopic debridement and posterior open capsulotomy - for the treatment of chronic extension deficits after ACLR and (2) to describe the surgical technique of posterior open release with both posteromedial and posterolateral approaches.

MATERIAL AND METHODS

This is a retrospective clinical cohort study. Twelve patients presenting a chronic flexion contracture of 10° or more after ACLR treated by open posterior arthrolysis with an average follow-up time of 38months (range six to 90) were included. At last follow-up, they underwent both a clinical examination with range of motion analysis, International Knee Documentation Committee (IKDC) and KOOS scores.

RESULTS

At follow-up, all patients except one (93%) achieved complete extension. Only one patient (7%) had a residual post-operative flexion deformity of five degrees. The range of motion (ROM) improved significantly after arthrolysis from 96°±14.3° (SD) to 14.3°±7°(SD)(p<0.001). No post-operative complications were recorded. No patients required further open debridement. The post-operative objective IKDC score was grade A for five patients, B for seven versus C for five patients and D for seven preoperatively. The mean post-operative subjective IKDC score was 86.4±9.7. The post-operative Knee injury and Osteoarthritis Outcome Score (KOOS) distribution was as follows: pain 93.8±5 (SD); symptoms 88±8.6 (SD); ADL 96.8±3.7 (SD); sports activities 83.6±12.3 (SD); and quality of life 82.9±8.8 (SD). Mean patients' satisfaction was 9.25±0.6 (SD) out of 10 after arthrolysis.

CONCLUSIONS

Open posterior release with both posteromedial and posterolateral approaches is a safe and efficient additional procedure in case of persistent flexion contracture after ACLR with good ROM gain, functional scores and patients' satisfaction.

LEVEL OF EVIDENCE

Therapeutic study - Level IV.

Does the hyperextension maneuver prevent knee extension loss after arthroscopic anterior cruciate ligament reconstruction?

Background

Disruption of the anterior cruciate ligament (ACL) is one of the most frequent musculoskeletal injuries affecting physically active men and women. In the United States, an estimated 200,000 ACL reconstructions are performed annually. One of the most common complications of ACL reconstruction is loss of extension. The purpose of this study was to assess the effects of the hyperextension maneuver on preventing knee extension loss after arthroscopic ACL reconstruction.

Materials and methods

In this prospective randomized clinical trial study, 100 adult patients with a documented complete ACL tear were randomized to two groups. All patients underwent arthroscopic ACL reconstruction with quadrupled semitendinosus and gracilis autograft by the senior author based on the same technique and instruments. However, the hyperextension maneuver was only performed in 50 patients during autograft fixation on the tibial side (case group). The postoperative rehabilitation protocol was similar for both groups. The knee range of motion and extension limit was evaluated at 2, 6, 12, and 24 weeks and at 1 year postoperatively.

Results

One hundred patients (88 male and 12 female) aged from 17−36 years (average 26.9 years) were included in our study. The two groups were similar regarding age, sex, and dominant side involvement (P >0.4).The difference between the two groups was significant only at 2 weeks (P <0.02). After 2 weeks, although the rate of limited extension was higher in the control group, no significant difference was seen between the groups.

Conclusion

Although the hyperextension technique during graft fixation on the tibial side may induce better range of motion in the first 2 weeks after ACL reconstruction surgery, this effect is not significant after 2 weeks.

Level of evidence

Therapeutic level II.

The use of early immobilization in the management of acute soft-tissue injuries of the knee: results of a survey of emergency physicians, sports medicine physicians and orthopedic surgeons

BACKGROUND

Evidence-based guidelines on the use of immobilization in the management of common acute soft-tissue knee injuries do not exist. Our objective was to explore the practice patterns of emergency physicians (EPs), sports medicine physicians (SMPs) and orthopedic surgeons (OS) regarding the use of early immobilization in the management of these injuries.

METHODS

We developed a web-based survey and sent it to all EPs, SMPs and OS in a Canadian urban centre. The survey was designed to assess the likelihood of prescribing immobilization and to evaluate factors associated with physicians from these 3 disciplines making this decision.

RESULTS

The overall response rate was 44 of 112 (39%): 17 of 58 (29%) EPs, 7 of 15 (47%) SMPs and 20 of 39 (51%) OS. In cases of suspected meniscus injuries, 9 (50%) EPs indicated they would prescribe immobilization, whereas no SMPs and 1 (5%) OS would immobilize (p = 0.002). For suspected anterior cruciate ligament injuries, 13 (77%) EPs, 2 (29%) SMPs and 5 (25%) OS said they would immobilize (p = 0.005). For lateral collateral ligament injuries, 9 (53%) EPs, no SMPs and 6 (32%) OS would immobilize (p = 0.04). All respondents would prescribe immobilization for a grossly unstable knee.

CONCLUSION

We found that EPs were are more likely to prescribe immobilization for certain acute soft-tissue knee injuries than SMPs and OS. The development of an evidenced- based guideline for the use of knee immobilization after acute soft-tissue injury may reduce practice variability.

Simultaneous Reconstruction of the Anterior Cruciate Ligament and Medial Collateral Ligament in Patients With Chronic ACL-MCL Lesions: A Minimum 2-Year Follow-up Study

BACKGROUND

In cases of chronic anterior cruciate ligament (ACL)-medial collateral ligament (MCL) lesions, nonoperative treatment of the MCL lesion may lead to chronic valgus instability and rotatory instability. The optimal management for patients who have combined ACL-MCL injuries remains controversial.

PURPOSE

To present a case series of 21 patients who underwent simultaneous ACL-MCL reconstruction with a 2- to 5-year follow-up.

STUDY DESIGN

Case series; Level of evidence, 4.

METHODS

From October 2007 to December 2010, a total of 21 patients with chronic ACL-MCL injuries, for which the 2 ligaments were reconstructed during the same surgical procedure, were studied. All patients were available for follow-up for at least 2 years. The International Knee Documentation Committee (IKDC) subjective knee scores, valgus and sagittal stability, anteromedial rotatory stability, range of motion, and complications were assessed both preoperatively and postoperatively.

RESULTS

At follow-up, valgus and sagittal laxity were not observed in any of the patients. The mean medial knee opening was significantly reduced to 0.80 ± 0.96 mm (range, -1.2 to 2.6 mm) postoperatively compared with 8.0 ± 1.3 mm (range, 6.1 to 10.7 mm) preoperatively (P < .01). The mean postoperative side-to-side difference measured with the KT-1000 arthrometer was reduced to 0.8 ± 0.9 mm (range, -1.2 to 2.3 mm) compared with 8.4 ± 1.6 mm (range, 6.2 to 13.2 mm) preoperatively (P < .01). Preoperative anteromedial instability was seen in 71% of patients (15/21), whereas none of the patients had anteromedial rotatory instability at the last follow-up. The mean IKDC subjective score improved overall from 45.3 ± 12.0 (range, 28.7-69.0) preoperatively to 87.7 ± 8.2 (range, 65.5-100.0) at the last follow-up (P < .01). Most patients (20/21) had normal or nearly normal range of motion of the knee joint; only 1 patient (5%) had a limitation of flexion of 15° compared with the contralateral knee at the last follow-up.

CONCLUSION

In patients with chronic ACL-MCL lesions, simultaneous reconstruction of the ACL and MCL can significantly improve the medial, sagittal, and rotatory stability of the knee at short-term follow-up.

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.

Recent advances in the rehabilitation of anterior cruciate ligament injuries

Rehabilitation following anterior cruciate ligament surgery continues to change, with the current emphasis being on immediate weight bearing and range of motion, and progressive muscular strengthening, proprioception, dynamic stability, and neuromuscular control drills. The rehabilitation program should be based on scientific and clinical research and focus on specific drills and exercises designed to return the patient to the desired functional goals. The goal is to return the patient's knee to homeostasis and the patient to his or her sport or activity as safely as possible. Unique rehabilitation techniques and special considerations for the female athlete will also be discussed. The purpose of this article is to provide the reader with a thorough scientific basis for anterior cruciate ligament rehabilitation based on graft selection, patient population, and concomitant injuries.

The influence of posterolateral rotatory instability on ACL reconstruction: comparison between isolated ACL reconstruction and ACL reconstruction combined with posterolateral corner reconstruction

BACKGROUND

The purpose of the present retrospective study was to evaluate the influence of posterolateral corner reconstruction on anterior cruciate ligament (ACL) reconstruction in terms of anterior laxity and clinical outcomes. We hypothesized that the effects of combined ACL and posterolateral corner reconstruction would be less satisfactory than those of isolated ACL reconstruction in terms of anterior laxity and clinical outcomes.

METHODS

We retrospectively studied sixty-nine patients who underwent ACL reconstruction from February 2001 to December 2005. Forty-six patients underwent isolated ACL reconstruction (Group I), and twenty-three patients underwent combined ACL and posterolateral corner reconstruction (Group II). Clinical outcomes were determined from data obtained before surgery and at the time of the twenty-four-month follow-up examination.

RESULTS

Postoperatively, the mean side-to-side difference (and standard deviation) in anterior tibial translation, measured with a KT2000 arthrometer, was greater for Group I (2.2 ± 1.0 mm) than for Group II (1.6 ± 0.8 mm) (p = 0.031). Seven knees (15.2%) in Group I and two knees (8.7%) in Group II had grade-1 anterior translation. The mean Lysholm score was 93.2 in Group I and 90.1 in Group II (p = 0.392). Thirty-eight knees (82.6%) in Group I and twenty knees (87.0%) in Group II were classified as normal or nearly normal according to the International Knee Documentation Committee scoring system (p = 0.882).

CONCLUSIONS

On the basis of the evaluation of ligamentous laxity with use of the KT2000 arthrometer, we observed that combined ACL and posterolateral corner reconstruction allows less anterior translation than isolated ACL reconstruction. However, we could not identify significant differences between the two groups in terms of functional outcomes.