Biomechanical analysis of an isolated fibular (lateral) collateral ligament reconstruction using an autogenous semitendinosus graft

An Anatomic Reconstruction of Both the Anterior Cruciate Ligament and Fibular Collateral Ligament Using Autografts

Fibular collateral ligament (FCL) tears rarely occur in isolation and are typically injured in conjunction with another ligament, including the anterior cruciate ligament (ACL). Reconstruction of both ACL and the FCL is critical to restore proper knee biomechanics and stability. This technique describes an anatomic reconstruction of both the ACL using a bone-patellar tendon-bone autograft and the FCL using a semitendinosus hamstring autograft. Previous biomechanical studies have reported on the effect of ACL and FCL tears on lateral gapping and the importance of reconstruction to restore near native stability. Outcomes studies have reported positive patient outcomes for both techniques individually and together.

Anatomic Fibular-Based Posterolateral Corner Reconstruction With 2 Femoral Tunnels Shows Lowest Residual Laxity With External Rotation and Varus Stresses: A Systematic Review and Network Meta-analysis of In Vitro Biomechanical Studies

PURPOSE

To perform a systematic review and network meta-analysis of in vitro cadaveric, biomechanical studies evaluating described techniques for posterolateral corner (PLC) reconstruction, including fibular- and tibiofibular-based techniques.

METHODS

The PubMed/MEDLINE, Embase, and Cochrane Library databases were searched in December 2023 for cadaveric studies evaluating PLC reconstruction. After a descriptive summary, a series of frequentist network meta-analyses comparing (1) nonanatomic fibular-based (single femoral tunnel), (2) anatomic fibular-based (double femoral tunnel), and (3) anatomic tibiofibular-based PLC reconstructions with the intact knee were performed for both external rotation (ER) and varus laxity from 0° to 90° of knee flexion. Pooled treatment estimates were calculated as mean differences (MDs) with 95% confidence intervals (CIs) using random-effects models.

RESULTS

A total of 31 studies were included. Nonanatomic fibular-based reconstructions showed increased ER laxity compared with the intact state between 30° and 90° of flexion (MD, 1.66° [95% CI, -0.27° to 3.59°] at 0° [P = .093]; MD, 2.29° [95% CI, 0.44° to 4.13°] at 30° [P = .015]; MD, 3.04° [95% CI, 0.95° to 5.12°] at 60° [P = .004]; and MD, 4.30° [95% CI, 1.41° to 7.19°] at 90° [P = .004]). The anatomic fibular- and tibiofibular-based reconstructions restored ER stability at all flexion values (except at 0° for tibiofibular based). All 3 reconstructions restored varus stability compared with the intact state in all scenarios except the anatomic fibular-based techniques at 0° (MD, 0.85° [95% CI, 0.06° to 1.63°]; P = .034). Across the assessed ER and varus laxity states, the anatomic fibular-based reconstruction was ranked "best" in 5 of 8 scenarios.

CONCLUSIONS

PLC reconstructions using nonanatomic fibular-based techniques showed increased residual laxity in ER from 30° to 90° of knee flexion. Conversely, anatomic fibular- and tibiofibular-based reconstructions showed ER and varus laxity similar to that in the intact knee state across most of the assessed knee flexion values.

CLINICAL RELEVANCE

Various techniques have been described for PLC reconstruction. However, no study has comprehensively compared the biomechanical properties of these reconstructions with one another.

Weight-Bearing Physical Activity, Lower-Limb Muscle Mass, and Risk of Knee Osteoarthritis

Importance

It has been demonstrated that total physical activity is not associated with risk of osteoarthritis. However, the association of different types of physical activity with incident knee osteoarthritis remains unclear.

Objective

To determine whether weight-bearing recreational physical activities are associated with increased risk of incident knee osteoarthritis.

Design, Setting, and Participants

This prospective cohort study used data from the Rotterdam Study (1996 to 2009), including participants with knee x-ray measurements at baseline and follow-up examinations. Participants with knee osteoarthritis at baseline were excluded. Residents aged 45 years and older of the Ommoord district in the city of Rotterdam in The Netherlands were invited to join the Rotterdam Study (78% response rate). Analysis was conducted in June 2023.

Exposure

Total, weight-bearing, and non-weight-bearing recreational physical activities collected by questionnaires at baseline.

Main Outcomes and Measures

Incident radiographic knee osteoarthritis measured by knee x-ray was the primary outcome, and incident symptomatic knee osteoarthritis defined by x-ray and knee pain questionnaire was the secondary outcome. The association of different types of recreational physical activity with radiographic knee osteoarthritis was examined using logistic regression within generalized estimating equation framework after adjusting for potential confounders. A prespecified stratification analysis was planned on the basis of lower-limb muscle mass index (LMI) tertiles, measured by dual-energy x-ray absorptiometry.

Results

A total of 5003 individuals (2804 women [56.0%]; mean [SD] age, 64.5 [7.9] years) were included. The knee osteoarthritis incident rate was 8.4% (793 of 9483 knees) for a mean (SD) follow-up time of 6.33 (2.46) years. Higher weight-bearing activity was associated with increased odds of incident knee osteoarthritis (odds ratio [OR], 1.22; 95% CI, 1.10-1.35; P < .001), but non-weight-bearing activity was not (OR, 1.04; 95% CI, 0.95-1.15; P = .37). In the analysis stratified by LMI tertiles, the association of weight-bearing activity with incident osteoarthritis was found only among 431 patients in the lowest LMI tertile (OR, 1.53; 95% CI, 1.15-2.04; P = .003), but not among patients in the middle or high LMI tertile.

Conclusions and Relevance

The findings of this study suggest that weight-bearing activity is associated with incident knee osteoarthritis in people with low levels of lower-limb muscle mass, which might be a promising avenue for tailored advice for physical activity.

Outcome of percutaneous reconstruction of chronic lateral collateral ligament rupture

PURPOSE

Many techniques have been described for the reconstruction of chronic lateral collateral ligament (LCL) rupture with different autograft options. The advantages of percutaneous LCL reconstruction include small incisions, minimal soft tissue disruption, less postoperative pain, and speedy rehabilitation and recovery. The aim of this study was to report the functional outcome of percutaneous LCL reconstruction and overall patient satisfaction in Africans.

METHODS

This prospective and interventional study involving 51 patients with chronic LCL rupture who had percutaneous LCL reconstruction using peroneus longus autograft was conducted between January 2021 and December 2022 in National Orthopaedic Hospital, Dala-Kano, Nigeria. The inclusion criteria were patients between the ages of 18 and 45 years with chronic isolated LCL and not more than 1 injury of knee ligament. Exclusion criteria were active infection, and multi-ligament knee injury requiring 2-staged surgery. The knee functions were assessed preoperatively, 3 months, 6 months, and 12 months postoperatively using the Lysholm scoring system. Patient satisfaction with the outcome of the treatment was assessed using a 5-point Likert scale. Relevant information was recorded into Microsoft Excel sheet and data was analyzed using SPSS version 23.0 for windows. The paired samples t-test was used to compare the clinical outcomes as continuous variables. Statistical significance was considered at p < 0.05.

RESULTS

The mean age of the patients was (30.10 ± 5.90) years. The median time from injury to surgery was 7 months (ranging from 3 to 28 months). The mean follow-up period was (14.07 ± 3.13) months. The mean preoperative and 1-year postoperative Lysholm scores were 44.33 ± 12.97 and 97.96 ± 1.23, respectively.

CONCLUSION

Percutaneous LCL reconstruction using peroneus longus autograft significantly improves patient knee function and results in excellent patient satisfaction.

Minimally Invasive Knee Lateral Collateral Ligament Reconstruction Using Partial Biceps Femoris Tendon Autograft

Lateral collateral ligament (LCL) is known as an important ligament to restrain varus force of the knee, especially in 30° knee flexion. From the anatomical study, the insertion of LCL at proximal fibula is intimately close to the insertion of biceps femoris (BF) tendon. Since LCL is infrequently injured in isolation, and with limitation in availability of autograft and allograft, this study proposes the partial anterior BF tendon as an alternative autograft source to reconstruct the LCL. This could be performed either by minimally invasive procedure or standard open technique. The core concept is to preserve the posterior part of the BF tendon to protect the peroneal nerve, by which exploration of this nerve and the proximal fibula prior to LCL reconstruction could be exempted. Minimally invasive LCL reconstruction using this autograft would essentially reduce soft tissue injury, shorten the operative time, and enhance recovery of the reconstructed knee.

Percutaneous Lateral Collateral Ligament Release for Arthroscopic Procedures of the Knee: The "Lateral Pie-Crusting"

Arthroscopy of the knee is among the most frequent procedures worldwide in orthopaedic surgery. To avoid iatrogenic cartilage injury, adequate visualization and working space are mandatory to perform complex procedures. Narrow femorotibial joint space is often encountered, and it is challenging to obtain consistent satisfactory results. Medial collateral ligament release is safe and reliable for facilitating medial joint widening. Current clinical studies support lateral collateral ligament (LCL) healing capacity in isolated injuries. This article describes a simple, safe, and reproducible technique of LCL release through a multiple-puncture method to facilitate lateral compartment visualization and instrumentation, the so-called lateral pie-crusting.

Anterior Cruciate Ligament Revision Surgery Associated to Lateral Collateral and Anterolateral Ligaments Reconstruction With Single Achilles Tendon Allograft and Single Femoral Tunnel

Lateral collateral ligament (LC) injuries that go unnoticed when associated with an anterior cruciate ligament (ACL) tear can increase stress forces on the ACL graft causing its failure. Furthermore, it is a main stabilizer to varus stress and external rotation. On the other hand, the reinforcement of anterolateral structures during ACL reconstruction has regained popularity in recent years, because evidence has shown that it increases the control of rotational laxity and decreases ACL graft failures, especially in revision surgery. The present article shows a technique to perform an ACL reconstruction, associated with the reconstruction of the LCL and of the anterolateral ligament using a single Achilles tendon allograft, which is split after the fixation of the ACL graft into two fascicles.

Synthetic graft for medial patellofemoral ligament reconstruction: a systematic review

Background

This systematic review investigates the role of synthetic graft for primary medial patellofemoral ligament (MPFL) reconstruction in patients with recurrent patellofemoral instability, focusing on clinical scores and the rate of complications.

Methods

This systematic review was conducted according to the PRISMA statement. The main online databases were accessed in January 2022 without time constraints. All clinical studies investigating the use of synthetic grafts for MPFL reconstruction were accessed. Revision settings were not considered. Only articles reporting data on patients with recurrent patellofemoral instability were eligible. Studies regarding congenital or acute patellofemoral dislocation were excluded. Only studies performing a follow-up longer than 24 months were considered.

Results

Data on 199 patients [mean age 22.3 (range 19.0–28.0) years] were collected. The mean follow-up was 60.5 (39.0–142.8) months. All the scores of interest improved at last follow-up: Kujala (+ 24.8; P = 0.0002), Lysholm (+ 42.0; P = 0.02), Tegner (+ 1.2; P = 0.03), IKDC (+ 20.9; P = 0.02). Post-operatively, a positive apprehension test was detected in 6.1% (7/115) of patients, and a sensation of instability was reported by 1.5% (3/199) of patients. The rate of re-dislocations was 2.5% (5 of 199 patients), and revision procedures were performed in less than 1% (1 of 199) of patients.

Conclusion

Synthetic graft may be reliable and feasible for primary MPFL reconstruction in patients with recurrent patellofemoral instability.

Imaging Characteristics of the Proximal Lateral Collateral Ligament of the Knee: Findings on Ultrasound and MRI With Histologic Correlation

OBJECTIVES

Determine prevalence of increased signal intensity of the lateral collateral ligament (LCL) of the knee on MRI and decreased echogenicity on ultrasound, and compare with cadaveric histologic evaluation.

METHODS

After IRB approval of this prospective study with informed consent, patients having knee MRI were additionally evaluated with ultrasound. Signal intensities of LCL on MRI (low, intermediate, high), echogenicity at ultrasound (hyperechoic, hypoechoic, anechoic), and extent of findings were assessed. Descriptive statistics, Wilcoxon signed ranked test, and intraclass correlation coefficient (ICC) were calculated. Two cadaveric knees were imaged with MRI and ultrasound, including histologic LCL evaluation.

RESULTS

Seventy-three subjects were included (39 males, 34 females; mean age 48 ± 14 years) with 77 knee examinations. On MRI, low, intermediate, and high signals were present in 21% (16/77), 75% (58/77), and 4% (3/77), respectively. On ultrasound, echogenicity was assessed as hyperechoic, hypoechoic, and anechoic in 62% (48/77), 38% (29/77), and 0% (0/77), respectively. Mean length of increased signal was 8.6 mm (±4.9) on MRI, and 6.5 mm (±4.8) on ultrasound. The ICC showed a good to excellent intermodality reliability (0.735-0.899) without statistically significant difference for interreader measurements (P = .163-.795). Histology evaluation showed transition of ligament fibers to fibrocartilage at its insertion with increased connective tissue mucin corresponding to MRI and ultrasound findings.

CONCLUSIONS

Increased signal intensity of the proximal LCL on ultrasound and MRI is common and corresponds to normal connective tissue mucin.

The gracilis and semitendinosus muscles: a morphometric study on 18 specimens with clinical implications

INTRODUCTION

The pes anserinus consists of the sartorius, semitendinosus, and gracilis muscles. They coalesce together with the leg fascia to form the anserine plate. The semitendinosus and gracilis both form the deep layer of this plate and are clinically relevant for ligament reconstruction. The aim of the study is to report a detailed morphometric evaluation of the semitendinosus and gracilis muscles and assess their clinical implications.

METHODS

Using a rigorous dissection process on 18 cadaveric hips, measurements of both the semitendinosus and gracilis muscles with bone parameters were conducted. We measured the following: (a) total femur, femoral shaft, and neck lengths, (b) total muscle lengths, and (c) intra-muscular and extra-muscular (free) tendon lengths. Correlation values between bone variables, muscle variables, and in-between muscle variables were computed.

RESULTS

The total muscle and the distal intra-muscular tendon length of the St and Gr are correlated with the total femur length. When compared to gracilis, the total muscle and distal intra-muscular tendon lengths of the ST are much better correlated with the total femur length. The free distal tendon length for both muscles did not show a significant correlation with any of the femoral bone lengths.

CONCLUSION

The variability of tendon length of the ST/Gr poses a significant challenge to surgeons. This study reports a detailed morphometric evaluation of the ST/Gr hamstring muscle and tendons. It revealed a positive correlation between the femoral length and the ST/Gr graft lengths. This could help orthopedic surgeons in predicting the graft lengths pre-operatively and develop better planning for reconstructive surgeries.

Fibular Collateral Ligament Reconstruction Graft Options: Clinical and Radiographic Outcomes of Autograft Versus Allograft

PURPOSE

To compare varus knee stability and clinical outcomes between patients who underwent fibular collateral ligament reconstruction (FCLR) or lateral collateral ligament (LCL) reconstruction with autografts versus allografts when undergoing concomitant anterior cruciate ligament reconstruction (ACLR).

METHODS

All patients who underwent primary ACLR and concomitant FCLR from 2010 to 2017 performed by a single surgeon (R.F.L.) were retrospectively identified. Clinical characteristics and graft choices for FCLR were collected. Patients with a minimum 2-year follow-up for clinical outcome scores and 6-month stress radiographs were included. Patients with any other ligamentous procedure or revision ACLR were excluded.

RESULTS

We identified 69 primary ACLR with concomitant FCLR patients who met the inclusion criteria. Fifty patients underwent FCLR with semitendinosus autografts, and 19 with allografts. There were no significant side-to-side differences (SSDs) in lateral compartment gapping on varus stress x-rays between the 2 cohorts (allograft, 0.49 mm; autograft, 0.15 mm, P = .22), and no FCLR failures. There were no significant differences between autograft and allograft groups at minimum 2-year outcomes for 12-Item Short Form mental or physical composite score (SF12 MCS, P = .134; SF12 PCS, P = .642), WOMAC total (P = .158), pain (P = .116), stiffness (P = .061), or activity (P = .252); International Knee Documentation Committee (IKDC) (P = .337), Tegner (P = .601), Lysholm (P = .622), or patient satisfaction (P = .218). There were no significant differences in clinical knee stability between groups at an average follow-up of 3.6 years (P = 1.0).

CONCLUSION

There were no differences in varus stress laxity 6 months postoperatively or clinical outcome scores at ≥2 years postoperatively between patients having FCL reconstructions with either autograft or allograft. This study demonstrates that both hamstring autografts and allografts for FCL reconstructions offer reliable and similar radiographic and clinical results at short-term follow-up.

LEVEL OF EVIDENCE

III, retrospective comparative trial.

Injury to the Popliteal Artery and Vein During Open Fibular Collateral Ligament Reconstruction: A Case Report

CASE

We present a case involving a 26-year-old male who sustained an iatrogenic injury to the right popliteal artery and vein during open fibular collateral ligament reconstruction. The lesions were repaired immediately and required subsequent procedures on postoperative day 1.

CONCLUSIONS

Iatrogenic vascular injuries during knee surgery can be devastating for patients and may lead to increased medical costs, unexpected hospital admissions, and additional surgical procedures. Surgeons should scrutinize preoperative imaging to identify the anatomic location of the popliteal artery and vein, which may be at risk during posterolateral knee reconstruction.

Every layer of quadriceps tendon's central and medial portion offers similar tensile properties than Hamstrings or Ilio-Tibial Band Grafts

PURPOSE

The aim of our cadaveric study was to compare the mechanical properties of different parts of the quadriceps' tendon in a load to failure analysis as compared to three other, and most common types of grafts that are used to perform ligament's reconstruction.

METHODS

Ten fresh-frozen cadavers (5 women, 5 men) were selected from our anatomical department. Mean age at death was 64 years (48-87 years). Tendons were harvested to prepare (1) different quadriceps tendon's specimens: lateral portion (QTlat), medial portion superficial layer (QTMsup) and deep layer (QTMdeep) and central portion superficial (QTCsup) and deep layers (QTCdeep) (2) Patellar Tendon (PT), (3) Gracilis+Semi-Tendinosus specimens (GST). Specimens were stored at - 40 °C in a freezing solution. Specimens were securely attached to a dedicated loading platform, measurements were done using a validated software. Load to failure testing was then carried out. Young's Elastic moduli, ultimate Stress (MPa) and Deformation (%) were analysed.

RESULTS

The elastic moduli of the PT was significantly higher than all other grafts, all medial and central QT layers (superficial and deep) were significantly higher than its lateral part (QTlat). In terms of Ultimate Stress, all grafts were significantly greater than QTlat, PT and GST were significantly superior to QT central portions and to ITB but there did not differ with the medial portion of QT. ITB ultimate stress values were significantly higher than QTlat. The ultimate deformations of all grafts were similar.

CONCLUSIONS

This study provides reference values in in order to characterize different parts of the QT that presents anatomically and Mechanically with complex characteristics. Every Layer of Quadriceps Tendon's Central and Medial Portion Offered Similar Mechanical Properties than Two Strand Hamstrings or Ilio-Tibial Band.

Editorial Commentary: Those Who Don't Know History Are Condemned to Repeat It-What Are the Next Steps to Improve Posterolateral Knee Outcomes?

Two decades ago, it was not uncommon to call the posterolateral corner of the knee the "dark side of the knee." This was because there were few quantitative anatomic data, no anatomic-based reconstructions, and a high rate of clinical outcome failures. Most nonanatomic posterolateral reconstruction procedures at the time commonly resulted in significant recurrent increases in varus gapping and significant overconstraint in external rotation. Postoperative protocols for treating these injuries were designed to often either cast or immobilize the operative knee for 2 to 6 weeks, which resulted in a higher incidence of arthrofibrosis. In addition, missed or neglected posterolateral corner injuries were frequently the cause of failed anterior and posterior cruciate ligament reconstruction graft failures. Anatomic-based posterolateral corner reconstructions have now been validated clinically to significantly improve patient outcomes. The next steps in improving patient outcomes would be to further refine these anatomic-based techniques, improve postoperative rehabilitation protocols, and ensure that future outcome studies have both patient-reported outcomes and objective data with stress radiographs to confirm that we are building a better mousetrap to treat this pathology.

Editorial Commentary: Shedding Light on the Posterolateral Corner of the Knee: Can We Do it With the Scope? Is There a Real Benefit?

Historically described as the "dark side of the knee," the posterolateral corner of the knee has been a significant focus of anatomic, biomechanical, and clinical outcomes research due to poor treatment outcomes for these injuries before improvements over the past 2 decades. These research efforts have resulted in significant improvements in the understanding, diagnosis, and surgical treatment of these injuries. Perhaps most importantly, improved understanding of the anatomy and biomechanics has led to the development of anatomic-based reconstructions, which have been subsequently validated with both biomechanical and clinical outcomes. Due to the complex anatomy and proximity of neurovascular structures, reconstructions have historically used large "hockey stick" incisions to provide adequate visualization to identify the anatomic insertions of the static stabilizers and ensure adequate protection of neurovascular structures. These anatomic-based techniques have significantly improved the clinical and objective outcomes of the surgical treatment of posterolateral knee injuries. However, as techniques have evolved and the clinical outcomes have improved, clinicians have attempted to develop and employ less-invasive and arthroscopically assisted techniques. Specifically, given the steep learning curve, paucity of clinical outcomes, increased operative time, and the limited view of the anatomy, which may increase the risk of nonanatomic tunnel placement, and injuries to surrounding structures, we cannot support an arthroscopic approach at this time.

Anatomic, All-Arthroscopic Reconstruction of Posterolateral Corner of the Knee: A Cadaveric Biomechanical Study

PURPOSE

To assess the role of anatomic reconstruction of the posterolateral corner (PLC) of the knee arthroscopically in cadaveric knees with simulated isolated grade III posterolateral instability.

METHODS

A total of 12 nonpaired, fresh-frozen cadaveric knees were biomechanically subjected to a 10-Nm varus moment, 5-Nm external and internal rotation torques, and 134-N posterior tibial load at 0°, 15°, 30°, 60°, and 90° of knee flexion (0° for varus loading only). Testing was performed with an intact and sectioned PLC and after anatomic reconstruction of the PLC by an arthroscopic technique. Kinematics of each knee under various loading conditions was determined with a robotic universal force/moment sensor testing system.

RESULTS

After sectioning, significant increases were found in varus rotation at 0°, 15°, 30°, 60°, and 90° of knee flexion; in external rotation at 15°, 30°, 60°, and 90° of knee flexion; in internal rotation at 60° of knee flexion only; and in posterior translation at 15° and 30° of knee flexion. After reconstruction, full recovery of knee stability was observed in varus rotation, external rotation, internal rotation, and posterior translation at all selected flexion angles without any overconstraint of knee kinematics.

CONCLUSIONS

Anatomic reconstruction of the PLC can be performed arthroscopically with isolated grade III posterolateral instability of the knee, and nearly normal stability of the knee can be restored.

CLINICAL RELEVANCE

PLC reconstruction by an anatomic, all-arthroscopic technique achieves optimal stability control and kinematics of the knee.

Graft choice for isolated MPFL reconstruction: gracilis versus semitendinosus

INTRODUCTION

After the first patellar dislocation, most patients report damage of the medio-patellofemoral ligament (MPFL) and surgical reconstruction is required. The purpose of this study is to systematically review current evidence and to clarify the role of the gracilis and semitendinosus tendons as graft for isolated MPFL reconstruction.

MATERIALS AND METHODS

The present systematic review was conducted according to the PRISMA guidelines. The literature search was conducted in October 2019. All clinical trials using the semitendinosus and/or gracilis tendon grafts for isolated MPFL reconstruction in patients with patellofemoral instability were considered for inclusion. Only articles reporting a minimum of 12-month follow-up were considered. The PEDro score was used for the methodological quality assessment.

RESULTS

Data from 1491 procedures were collected. The mean follow-up was 36.12 months. There was comparability among the patient baseline. All the scores of interests (Kujala, Tegner, Lysholm) and range of motion scored better in the semitendinosus group. Moreover, in favour of the semitendinosus group, a statistically significant reduction of the revision surgeries and re-dislocations were evidenced. Apprehension test and persistent instability sensation found any statistical correlations.

CONCLUSION

Isolated MPFL reconstruction through semitendinosus tendon graft performed better than the gracilis in selected patients suffering from recurrent patellofemoral instability.

Knee and Leg Injuries

Knee and leg injuries are extremely common presentations to the emergency department. Understanding the anatomy of the knee, particularly the vasculature and ligamentous structures, can help emergency physicians (EPs) diagnose and manage these injuries. Use of musculoskeletal ultrasonography can further aid EPs through the diagnostic process. Proper use of knee immobilizers can also improve long-term patient outcomes.

Arthroscopic-assisted anatomical reconstruction of the posterolateral corner of the knee joint

Several surgical techniques have been suggested to anatomically reconstruct the posterolateral corner of the knee joint. However, most of them are open techniques that require dissection of the skin and soft tissues without utilizing the advantages of arthroscopic-assisted techniques. Therefore, this study aimed to describe a novel arthroscopic technique that anatomically reconstructs the posterolateral corner of the knee joint. This novel arthroscopic technique can properly identify important landmarks for reconstruction and anatomically reconstruct the three key components (lateral collateral ligament, popliteus tendon, and popliteofibular ligament) of the posterolateral corner of the knee joint.

Treatment and outcomes of lateral collateral ligament injury associated with anterior and posterior cruciate ligament injury at 2-year follow-up

Background

Injuries to the lateral collateral ligament (LCL) are most commonly associated with anterior cruciate ligament (ACL) injury than with posterior cruciate ligament (PCL) injury. There is currently a paucity in the literature in regards to treatment and outcomes of such lesions.

Methods

30 patients underwent surgical treatment of concomitant LCL and ACL injury or concomitant LCL and PCL injury with follow-up postoperative period of two years. The Lysholm score and varus stress radiographs was calculated and analysed before and at 6, 12, and 24 months postoperatively.

Results

There was a significant increase in scores between two timepoints over the follow-up period for both groups: before surgery and after 6 months, and between 6 and 12 months (p < 0.05). The lateral joint opening measured on the varus stress radiographs was greater in group 2 than in group 1 before surgery (p = 0.04). When assessing each group separately, the lateral joint opening decreased at each timepoint in the first year for both groups (p < 0.05).

Conclusion

Patients diagnosed with combined LCL and PCL injuries were shown to have a higher degree of lateral opening at the time of injury when compared to patients with combined LCL and ACL injuries. However, there was no difference in lateral joint opening on stress radiography after 12 months postoperatively in either group. Finally Lysholm scores for both groups significantly increased between the preoperative period and 6 months postoperatively, as well as between 6 months and 12 months postoperatively.

Level of evidence

III.

Fibular Collateral Ligament Reconstruction in Adolescent Patients

Fibular collateral ligament (FCL) injuries can present as lateral-sided knee pain with feelings of side-to-side instability during activity. Patients with FCL injuries can have accompanying symptoms related to irritation of the common peroneal nerve. Preoperative diagnosis is imperative and should include a thorough physical examination complemented with varus stress radiographs before surgical reconstruction is indicated. In the adolescent cohort, surgical planning can be complicated by the presence of open physes, and caution must be taken to avoid drilling through or placing screw fixation across the physes. Potential complications include growth arrest and limb length discrepancy. Therefore, the purpose of this Technical Note is to describe an anatomic FCL reconstruction technique in the skeletally immature adolescent patient.

Fibular Collateral Ligament/ Posterolateral Corner Injury: When to Repair, Reconstruct, or Both

The posterolateral corner (PLC) of the knee was regarded as the "dark side" of the knee because of limited understanding of its anatomy and biomechanics and because of poor outcomes after injuries to PLC structures. These injuries rarely occur in isolation, with 28% reported as isolated PLC injuries. Nonoperative treatment of these injuries has led to persistent instability, development of early osteoarthritis, and poor outcomes. Several techniques for reconstruction of the PLC have been described, and all are reported to improve outcomes. Biomechanically validated anatomic reconstructions are preferred because they restore native knee kinematics and improve clinical outcomes without over-constraining the knee.

Validation of a novel biomechanical test bench for the knee joint with six degrees of freedom

A novel biomechanical test bench has been developed for in-vitro evaluation of the knee joint. The test bench allows the kinematics of the knee joint to be studied in all six degrees of freedom. Flexion-extension knee movements are induced by quadriceps and hamstring muscle forces simulated by five pneumatic cylinders. The kinematics of the knee and the actively applied muscle forces are measured simultaneously. The aim of this study was to validate the sensitivity and reproducibility of this novel test bench. Four fresh frozen human knees were tested three times, each with seven flexion-extension cycles between 5° and 60°. After the native knees had been tested, the posterior cruciate ligament and then the lateral collateral ligament were dissected. The injured knees were tested in identical conditions [3×(7×5°-60°)] in order to evaluate whether the test bench is capable of detecting differences in knee kinematics between a native state and an injured one. With regard to reproducibility, the novel test bench showed almost perfect agreement for each specimen and for all states and flexion angles. In comparison with the native knees, the injured knees showed significant differences in knee kinematics. This validated novel test bench will make it possible to investigate various knee pathologies, as well as current and newly developed treatment options.

Editorial Commentary: Small Incisions Can Make Big Mistakes: Knee Lateral Collateral Ligament Reconstruction Is All About the Anatomy!

It is becoming increasingly recognized that isolated lateral collateral ligament (LCL) tears are more common than have been previously recognized and that anatomic-based LCL reconstructions have the best outcomes. Although it was believed that posterolateral corner injuries were often missed or mistreated and were given the pneumonic of "the dark side of the knee," we are getting to the point where most of these more severe injuries are being recognized, and it is the isolated LCL injuries that are still less well recognized. Failure to treat LCL tears at the same time as a cruciate ligament reconstruction is a well-known cause of both anterior cruciate ligament and posterior cruciate ligament reconstruction graft failure. Therefore, either having the required clinical experience or knowledge, or using a radiographic backup method when one is not sure about the anatomic placement, is essential to correctly perform an LCL reconstruction.

Return to Play After Multiligament Knee Injuries in National Football League Athletes

Background:

Return to play (RTP) of National Football League (NFL) athletes after isolated anterior cruciate ligament (ACL) tears has been reported. However, no studies have reported on RTP of NFL athletes after multiligament knee injuries.

Hypotheses:

NFL athletes with multiligament knee injuries have lower RTP rates and longer recoveries than athletes with isolated ACL tears. Second, athletes with ACL and medial collateral ligament (MCL) injuries will have higher RTP rates and shorter time to RTP than athletes with an ACL tear and posterolateral corner involvement.

Study Design:

Retrospective cohort study.

Level of Evidence:

Level 4.

Methods:

Publicly available NFL injury data were reviewed for all multiligament knee injuries incurred between 2000 and 2016 with RTP information. Athletes were excluded if RTP was limited for reasons unrelated to the injury. Extracted data included type of injury, RTP, time to RTP (days), number and percentage of games played, and performance.

Results:

A total of 50 NFL athletes with multiligament knee injuries met inclusion and exclusion criteria. The overall RTP rate was 64.0%. Athletes with ACL/MCL tears had an RTP rate of 70.8%, whereas athletes with ACL and posterior collateral ligament/lateral collateral ligament (PCL/LCL) tears had an RTP rate of 55.6% (P = 0.26). Mean time to RTP for all 50 athletes was 388.71 ± 198.52 days. The mean time to RTP for athletes with ACL/MCL injuries was 305.1 ± 58.9 days, compared with 459.2 ± 245.1 days (P = 0.004) and 609.3 ± 183.1 days (P < 0.0001) for those with combined ACL and PCL/LCL injuries and frank knee dislocations, respectively. Athletes with ACL/MCL injuries were more likely to return to prior performance level (43.5%) than those with ACL and PCL/LCL injuries (18.5%) (P < 0.001).

Conclusion:

The RTP rate for athletes with multiligament knee injuries is significantly less than the RTP rate for athletes with isolated ACL tears. In addition, athletes with ACL and MCL tears have a higher RTP rate, a significantly shorter time to RTP, and a greater likelihood of returning to prior performance than athletes with ACL and PCL/LCL tears.

Clinical Relevance:

Multiligament knee injuries significantly affect the ability of a football player to return to sport. ACL and MCL tears are associated with better RTP prognosis compared with ACL and PCL/LCL tears.

Lateral Collateral Ligament Injury About the Knee: Anatomy, Evaluation, and Management

The lateral collateral ligament is the primary varus stabilizer of the tibiofemoral joint. Diagnosing an injury to this ligament can be challenging in the setting of multiligamentous trauma; however, failure to recognize these injuries can result in instability of the knee and unsatisfactory outcomes after cruciate ligament reconstruction. Recent literature exploring the anatomy and biomechanics of the lateral collateral ligament has enhanced our understanding and improved diagnosis and management of these injuries. Physical examination and imaging studies also are important in diagnosis and can facilitate classification of lateral collateral ligament tears, which affects treatment decisions. Nonsurgical, reparative, and reconstructive techniques can all be used to manage lateral collateral ligament injury about the knee; the optimal treatment is selected on the basis of injury severity.

Midterm outcomes following anatomic-based popliteus tendon reconstructions

PURPOSE

The purpose of this study was to document subjective outcomes following anatomic-based reconstruction of the popliteus tendon when the popliteus tendon was the only injured posterolateral knee structure. It was hypothesized that popliteus tendon reconstruction would result in improved patient outcomes after surgery regardless of the concurrent ligamentous or intra articular pathology.

METHODS

A consecutive series of 5 patients with a median age of 23 years (range, 22-36 years) who underwent anatomic popliteus tendon reconstruction along with concomitant ligament reconstruction or meniscus repair (if needed) were included in this study. All patients completed pre-operative and post-operative subjective questionnaires, which included the Lysholm score to document function, the Tegner activity scale to document activity level, and a patient satisfaction with outcome question.

RESULTS

All patients were available for a final follow-up at a median time of 2.8 years (range, 2-3.9 years) following the index surgery. Three patients had a combined popliteus tendon and posterior cruciate ligament reconstruction. Two of the three PCL reconstructions were revision procedures. The Lysholm score improved to from 53 (range, 34-90) to 91 (range, 44-100) at post-operative follow-up. The median pre-operative Tegner activity scale improved from 3 (range, 0-9) to a median score of 4.8 (range, 2-7) at post-operative follow-up. The median patient satisfaction with outcome was 9 (range, 7-10). The dial test at 30° and 90° improved in all patients following surgery.

CONCLUSIONS

Anatomic-based popliteus tendon reconstructions resulted in improved outcomes and a high patient satisfaction in patients with a complete tear of the popliteus tendon and symptomatic knee instability.

LEVEL OF EVIDENCE

IV, case series.

Return to National Basketball Association Competition Following Anterior Cruciate Ligament and Fibular Collateral Ligament Injuries: A Case Report

CASE

Numerous outcome studies regarding anterior cruciate ligament (ACL) reconstruction demonstrate the ability of athletes to return to a high level of play. However, to our knowledge, there is limited literature regarding return to play following injury to both the ACL and the fibular collateral ligament (FCL). We describe the case of a National Basketball Association (NBA) player who sustained a combined ACL and FCL knee injury and subsequently underwent surgical reconstruction of both affected ligaments. He was able to return to a preinjury level of competition at 9 months postoperatively.

CONCLUSION

It is possible for athletes to return to competitive basketball and maintain a high production level following a single-staged reconstruction of both the ACL and the FCL.

The Heel Height Test: A Novel Tool for the Detection of Combined Anterior Cruciate Ligament and Fibular Collateral Ligament Tears

PURPOSE

To determine the exact value of side-to-side difference (SSD) in heel height that was associated with combined anterior cruciate ligament (ACL) and fibular collateral ligament (FCL) tears (compared with an isolated ACL tear) and determine the clinical utility of heel height SSD in the assessment of this injury pattern.

METHODS

Two patient groups were identified: (1) patients with isolated ACL tears and (2) patients with combined ACL-FCL tears but without additional collateral or cruciate ligament injuries. Determination of the amount of the heel height SSD was determined during the outpatient clinic visit. Receiver operator characteristic curves were used to evaluate the accuracy of diagnostic tests by plotting the true-positive (sensitivity) rate against the false-positive (1-specificity) rate at various thresholds. In addition, magnetic resonance imaging (MRI) reports were reviewed to calculate the sensitivity of MRI for the detection of FCL injury. MRI sensitivity was then compared with the sensitivity of the heel height examination.

RESULTS

One hundred and fifty-eight patients (71 men, 87 women) in the isolated ACL tear patient group and 117 patients (60 men, 57 women) in the combined ACL-FCL tear patient group were reviewed. A 3-cm or greater SSD was found in 13 of the 158 (8.2%) isolated ACL tear patients and 84 of the 117 (72%) ACL-FCL tear patients. The sensitivity, specificity, positive predictive value, and negative predictive value of the heel height test were 72%, 92%, 86%, and 86%, respectively. The area under the receiver operator characteristic curve was found to be 0.876. After review of all preoperative MRI musculoskeletal radiology reports for patients in the ACL-FCL patient group, a sensitivity of 48% was found.

CONCLUSIONS

The clinical heel height test resulted in high sensitivity and excellent specificity for the diagnosis of combined ACL-FCL tears compared with the sensitivity and specificity of the MRI detection of FCL injury. The information presented in the current study will improve diagnostic ability through a simple physical examination and avoid missed injuries that are known to compromise surgical outcomes.

LEVEL OF EVIDENCE

Level III, cross-sectional.

Mechanical Analysis of Extra-Articular Knee Ligaments. Part One: Native knee ligaments

BACKGROUND

The aim of this study was to provide a characterization of the tensile properties of the medial collateral ligament (MCL), lateral collateral ligament (LCL), anterolateral ligament (ALL) and medial patellofemoral ligament (MPFL). Our hypothesis was that extra-articular knee ligaments are heterogeneous in nature and possess distinct material properties.

METHODS

MCL (n=12), LCL (n=11), MPFL (n=12) and ALL (n=19) samples from fresh frozen human cadaveric knees were subjected to uniaxial tensile testing to failure and analyzed for their material properties. The elastic modulus (slope of the linear portion of the stress/strain curve), ultimate stress (stress at failure), ultimate strain (strain at failure) and strain energy density (area under the stress/strain curve) were calculated.

RESULTS

The MCL had the highest elastic modulus (441.8±117.2MPa) and was significantly greater than the MPFL (294.6±190.4MPa) and LCL (289.0±159.7MPa) (P<0.05) as well as the ALL (173.7±91.8MPa) (P<0.001). The ultimate stress was significantly higher (P<0.05) for the LCL (83.6±38.1MPa) and MCL (72.4±20.7MPa), relative to the MPFL (49.1±31.0MPa) and ALL (46.4±20.1MPa). The ultimate strain of the LCL (41.0±9.9%) and ALL (37.8±7.9%) were significantly higher (P<0.05) compared to the MCL (22.9±2.5%) and MPFL (22.2±5.6%). The strain energy density of the LCL (15.2±6.4MPa) was significantly greater (P<0.05) than all other ligaments (ALL 7.8±3.1MPa, MCL 7.5±2.9MPa and MPFL 5.0±2.9MPa).

CONCLUSIONS

Extra-articular knee ligaments are a heterogeneous group with respect to material characteristics. Each ligament has tensile properties that are significantly different from others and treatment strategies should take these findings into account.

Mechanical Analysis of Extra-Articular Knee Ligaments. Part two: Tendon grafts used for knee ligament reconstruction

OBJECTIVES

The aim of this study was to provide information about the mechanical properties of grafts used for knee ligament reconstructions and to compare those results with the mechanical properties of native knee ligaments.

METHODS

Eleven cadaveric knees were dissected for the semitendinosus, gracilis, iliotibial band (ITB), quadriceps and patellar tendon. Uniaxial testing to failure was performed using a standardized method and mechanical properties (elastic modulus, ultimate stress, ultimate strain, strain energy density) were determined.

RESULTS

The elastic modulus of the gracilis tendon (1458±476MPa) (P<0.001) and the semitendinosus tendon (1036±312MPa) (P<0.05) was significantly higher than the ITB (610±171MPa), quadriceps tendon (568±194MPa), and patellar tendon (417±107MPa). In addition, the ultimate stress of the hamstring tendons (gracilis 155.0±30.7MPa and semitendinosus 120.1±30.0MPa) was significantly higher (P<0.001, respectively P<0.05), relative to the ITB (75.0±11.8MPa), quadriceps tendon (81.0±27.6MPa), and patellar tendon (76.2±25.1MPa). A significant difference (P<0.05) could be noticed between the ultimate strain of the patellar tendon (24.6±5.9%) and the hamstrings (gracilis 14.5±3.1% and semitendinosus 17.0±4.0%). No significant difference in strain energy density between the grafts was observed.

CONCLUSIONS

Material properties of common grafts used for knee ligament reconstructions often differ significantly from the original knee ligament which the graft is supposed to emulate.

Multiligament Knee Injuries in Older Adolescents: A 2-Year Minimum Follow-up Study

Background:

Multiligament knee injuries cause significant functional impairment. Adults undergoing anatomic reconstruction of multiligament knee injuries have excellent outcomes postoperatively. However, less is known about the outcomes in adolescent patients following multiligament reconstruction.

Purpose/Hypothesis:

We aimed to assess patient outcomes and failure rates following unstaged multiligament reconstruction in an adolescent population at a minimum 2-year follow-up. We hypothesized that outcomes of multiligament reconstruction in these patients would be comparable to previously reported outcomes in the adult population.

Study Design:

Case series; Level of evidence, 4.

Methods:

The study included patients who had undergone multiligament knee reconstruction at 19 years of age or younger and had at least 2 years of follow-up. All procedures were performed by the same surgeon. Exclusion criteria included patient age 14 years or younger at the time of surgery, open physes, prior ipsilateral meniscal or knee ligament surgery, or a tibial plateau fracture at the time of injury. Multiligament reconstruction was defined as a reconstruction of at least 1 cruciate ligament and at least 1 component of the posterolateral corner or the medial knee. Patients were evaluated according to Lysholm score, Tegner score, Short Form–12 physical component summary (SF-12 PCS), Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) score, and postoperative patient satisfaction.

Results:

Twenty patients (mean age, 17.7 years; mean follow-up, 37.1 months) were included in this study. No patient required additional ligament surgery after the index surgery because of graft failure. The median preoperative Lysholm score was 49.5 (range, 18-90), and the median postoperative Lysholm score was 86 (range, 44-100) (P < .001). The median preoperative Tegner activity score was 2 (range, 0-9), and the median postoperative Tegner activity score was 6 (range, 2-10) (P = .012). The median SF-12 PCS improved from 40.5 preoperatively to a median of 56.1 postoperatively (P < .001). WOMAC total score improved from a median of 26.5 preoperatively to a median of 2 postoperatively (P < .001). Median postoperative patient satisfaction was 10 (range, 5-10).

Conclusion:

Single-stage multiligament knee reconstruction is a reliable procedure that improves knee function at 2-year follow-up in adolescent patients. Patient satisfaction was excellent, but longer follow-up in a larger series of patients is required to determine the long-term benefits of multiligament reconstruction in this patient population.

Validation of varus stress radiographs for anterior cruciate ligament and posterolateral corner knee injuries: A biomechanical study

PURPOSE

The purpose of this study was to determine the effect of isolated anterior cruciate ligament (ACL) insufficiency on the radiographic varus stress test, and to provide reference data for the increase in lateral compartment opening under varus stress for a combined ACL and PLC injury.

METHODS

Ten cadaveric lower extremities were fixed to a jig in 20° of knee flexion. Twelve Newton-meter (Nm) and clinician-applied varus loads were tested, first with intact knee ligaments, followed by sequential sectioning of the ACL, fibular collateral ligament (FCL), popliteus tendon and the popliteofibular ligament (PFL). Lateral compartment opening was measured after each sequential sectioning.

RESULTS

Maximum increase in lateral compartment opening for an isolated ACL deficient knee was 1.06mm with mean increase of 0.52mm (p=0.021) for the clinician-applied load. Mean increase in lateral compartment opening in an ACL and FCL deficient knee compared to the intact knee was 1.48mm (p<0.005) and 1.99mm (p<0.005) for the 12-Nm and clinician-applied loads, respectively, increasing to 1.94mm (p<0.005) and 2.68mm (p<0.005) with sectioning of the ACL and all PLC structures.

CONCLUSIONS

Anterior cruciate ligament deficiency contributes to lateral compartment opening on varus stress radiographs though not sufficiently to confound previously established standards for lateral ligament knee injuries. We did not demonstrate the same magnitude of lateral compartment opening with sectioning of the PLC structures as previously reported, questioning the reproducibility of varus stress radiographic testing among institutions. Clinicians are cautioned against making surgical decisions based solely on current standards for radiographic stress examinations.

Anatomic Fibular Collateral Ligament Reconstruction

Fibular collateral ligament (FCL) injuries can lead to varus instability of the knee, causing a varus thrust gait and resulting in increased forces on the medial compartment of the knee. In the long term, this can result in meniscal injuries and medial compartment osteoarthritis. Varus instability is also reported to increase forces on the cruciate ligaments, which can lead to overload and failure of these reconstructions in cases of nonrecognized combined injuries. Historically, both repair and reconstruction have been used for grade III injuries to the FCL. However, repair has been reported to lead to a higher reoperation rate. The hereby presented reconstruction technique is used for FCL injuries that do not involve other structures of the posterolateral corner, but can be used in combination with other knee ligament reconstructions including the posterior cruciate ligament, anterior cruciate ligament, and medial collateral ligament. The purpose of this surgical technique article was to describe the biomechanically validated anatomic reconstruction of the FCL using a semitendinosus graft.

Influence of increasing construct constraint in the presence of posterolateral deficiency at knee replacement: A biomechanical study

When faced with posterolateral corner (PLC) deficiency, surgeons must choose a total knee replacement (TKR) construct that provides the appropriate level of constraint. This should match the internal constraint of the device to the soft tissue host laxity pattern. Little guidance is available peroperatively, with factors influencing final component choice remaining ill defined. This study aimed to quantify the effect of PLC insufficiency on the "envelope of laxity" (EoL) after TKR and the effect of increasingly component constraint upon knee behavior through a functional arc of flexion. Using computer navigation, mixed effect modeling and loaded cadaveric legs--laxity was quantified under separate states: the native knee, after implantation of a posterior stabilized (PS)-TKR, after sectioning the lateral (fibular) collateral ligament and popliteus tendon (PS-TKR-PLC), and after re-implantation with a semi-constrained "total stabilized" knee replacement (TS-TKR). Laxity was quantified from 0 to 110° of flexion for anterior draw, varus-valgus, and internal-external rotation. Implantation of the PS-TKR was consistently associated with increased constraint when compared to the native knee. PLC sectioning led to significantly increased laxity during varus stress from mid to deep flexion. Revision to a TS-TKR construct restored constraint mimicking that of the primary state but only for the arc of motion 0-90°. In a posterolateral deficient state, a fixed bearing semi-constrained TS-TKR restored the knee to near normal kinematics but this was only achieved from an arc of motion 0-90° of flexion. At higher flexion angles, there remained an unfavorable laxity pattern with varus stress opening.

A physeal-sparing fibular collateral ligament and proximal tibiofibular joint reconstruction in a skeletally immature athlete

The purpose of this report was to describe the surgical technique for and outcomes after a modified physeal-sparing posterolateral corner reconstruction in a 12-year-old skeletally immature male with a mid-substance fibular collateral ligament tear, a proximal posterior tibiofibular ligament tear, and an anterior cruciate ligament avulsion fracture of the medial tibial eminence. A modified physeal-sparing posterolateral corner reconstruction was used to provide a near-anatomic reconstruction of the fibular collateral ligament and proximal posterior tibiofibular ligament. An anterior cruciate ligament repair was also performed. Varus stress radiographs obtained at 6 months postoperatively demonstrated resolution of lateral knee stability. Physical examination results demonstrated stability to anterior tibial translation and a stable proximal tibiofibular joint. Computed tomography showed that the surgical technique successfully avoided breeching the patient's physes.

Anteromedial rotatory laxity

This paper describes anteromedial rotatory laxity of the knee joint. Combined instability of the superficial MCL and the structures of the posteromedial corner is the pathological background anteromedial rotatory laxity. Anteromedial rotatory instability is clinically characterized by anteromedial tibial plateau subluxation anterior to the corresponding femoral condyle. The anatomical and biomechanical background for anteromedial laxity is presented and related to the clinical evaluation, and treatment decision strategies are mentioned. A review of the clinical studies that address surgical treatment of anteromedial rotatory instability including surgical techniques and clinical outcomes is presented. Level of evidence V.

Clinically relevant anatomy and what anatomic reconstruction means

BACKGROUND

Within the past 20 years, knee ligament injuries have been increasingly reported in the literature to be treated with anatomic reconstructions over soft tissue advancements or sling-type procedures to recreate the native anatomy and restore knee function. Historically, early clinician scientists published on the qualitative anatomy of the knee, which provided a foundation for the initial knee biomechanical studies in the nineteenth and twentieth centuries. Similarly, the work of early sports medicine orthopaedic clinician scientists in the late twentieth century formed the basis for the quantitative anatomic and functional robotic biomechanical studies found currently in the sports medicine orthopaedic literature. The development of an anatomic reconstruction first requires an appreciation of the quantitative anatomy and function of each major stabilizing component of the knee.

PURPOSE

This paper provides an overview of the initial qualitative anatomic studies from which the initial knee ligament surgeries were based and expands to recent detailed quantitative studies of the major knee ligaments and the renewed recent focus on anatomic surgical reconstructions.

CONCLUSIONS

Anatomic repairs and reconstructions of the anterior cruciate ligament, posterior cruciate ligament, medial collateral ligament and posterolateral corner attempt to restore knee function by rebuilding or restoring the native anatomy. The basis of anatomic reconstruction techniques is a detailed understanding of quantitative knee anatomy. Additionally, an appreciation of the function of each component is necessary to ensure surgical success.

LEVEL OF EVIDENCE

V.

Outcomes following anatomic fibular (lateral) collateral ligament reconstruction

PURPOSE

The purpose of this study was to investigate clinical outcomes following anatomic fibular (lateral) collateral ligament (FCL) reconstruction. It was hypothesized that anatomic FCL reconstruction would result in improved subjective clinical outcomes and a high patient satisfaction with outcome.

METHODS

All patients 18 years or older who underwent FCL reconstruction from April 2010 to January 2013 with no other posterolateral corner pathology were included in this study. Patient subjective outcome scores were collected preoperatively and at a minimum of 2 years postoperatively.

RESULTS

There were 43 patients (22 males, 21 females, median age = 28.3 years, range 18.7-68.8) included in this study. The median time from injury to surgery was 22 days. Follow-up was obtained for 88 % of patients (n = 36) with a mean follow-up of 2.7 years. The mean Lysholm score significantly improved from 49 (range 11-100) to 84 (range 55-100) postoperatively (p < 0.001). The mean WOMAC score significantly improved from 37 (range 3-96) to 8 (range 0-46) postoperatively (p < 0.001). The median SF-12 physical component subscale score significantly improved from 35 (range 22-58) to 56 (range 24-62) postoperatively (p < 0.001). The median SF-12 mental component subscale score did not show significant change preoperatively 54 (range 29-69) to postoperatively 55 (range 25-62). The median preoperative Tegner activity scale improved from 2 (range 0-10) to 6 (range 2-10) postoperatively (p < 0.001). The median patient satisfaction with outcome was 8 (range 1-10). Postoperative patient-reported outcome scores were not significantly different for patients who underwent concomitant ACL reconstruction compared to patients without ACL reconstruction.

CONCLUSION

An anatomic FCL reconstruction with a semitendinosus graft significantly improved patient function and yielded high patient satisfaction in the 43 patients. Additionally, there was no significant difference in patient-reported outcomes when accounting for concomitant ACL reconstruction.

LEVEL OF EVIDENCE

Level IV.

Isolated lateral collateral ligament complex injury in rock climbing and Brazilian Jiu-jitsu

We report two occurrences of high-grade tears of the lateral collateral ligament complex (LCLC), consisting of the anterolateral ligament (ALL) and fibular collateral ligament (FCL). One injury occurred in a rock climber and the other in a martial artist. Increasing awareness of isolated injuries of the LCLC will allow for appropriate diagnosis and management. We review and discuss the anatomy of the LCLC, the unique mechanism of isolated injury, as well as physical and imaging examination findings.

In situ forces and length patterns of the fibular collateral ligament under controlled loading: an in vitro biomechanical study using a robotic system

PURPOSE

The aim of this study was to determine the in situ forces and length patterns of the fibular collateral ligament (FCL) and kinematics of the knee under various loading conditions.

METHODS

Six fresh-frozen cadaveric knees were used (mean age 46 ± 14.4 years; range 20-58). In situ forces and length patterns of FCL and kinematics of the knee were determined under the following loading conditions using a robotic/universal force-moment sensor testing system: no rotation, varus (10 Nm), external rotation (5 Nm), and internal rotation (5 Nm) at 0°, 15°, 30°, 60º, 90°, and 120° of flexion, respectively.

RESULTS

Under no rotation loading, the distances between the centres of the FCL attachments decreased as the knee flexed. Under varus loading, the force in FCL peaked at 15° of flexion and decreased with further knee flexion, while distances remained nearly constant and the varus rotation increased with knee flexion. Using external rotation, the force in the FCL also peaked at 15° flexion and decreased with further knee flexion, the distances decreased with flexion, and external rotation increased with knee flexion. Using internal rotation load, the force in the FCL was relatively small across all knee flexion angles, and the distances decreased with flexion; the amount of internal rotation was fairly constant.

CONCLUSIONS

FCL has a primary role in preventing varus and external rotation at 15° of flexion. The FCL does not perform isometrically following knee flexion during neutral rotation, and tibia rotation has significant effects on the kinematics of the FCL. Varus and external rotation laxity increased following knee flexion. By providing more realistic data about the function and length patterns of the FCL and the kinematics of the intact knee, improved reconstruction and rehabilitation protocols can be developed.

Isolated fibular collateral ligament injuries in athletes

Isolated injuries to the fibular collateral ligament (FCL) are rare. Although recent data suggest that operative and nonoperative treatment can both result in good functional outcomes, limited data exist on return to play for nonoperative treatment of FCL injuries and the value of magnetic resonance imaging in predicting prognosis. In this article, we present a review of the current literature and present a focused review regarding the diagnosis, treatment, and prognosis of FCL injuries, as well as the senior authors experience and a cohort of National Football League players. Magnetic resonance imaging can be useful to predict the length of disability in isolated FCL injuries, and both operative and nonoperative management of isolated FCL injuries successfully resulted in return to play in all players in several series of elite athletes; however, nonoperative management may result in faster return to play. Evaluation of potential concomitant injury is imperative in treatment of FCL injuries.

The fibular collateral ligament of the knee: a detailed review

The fibular collateral ligament (FCL) is one of the larger ligaments of the knee. The FCL, along with the popliteus tendon, arcuate popliteal ligament, and joint capsule, make up the posterolateral corner of the knee. Recently, there has there been an increased awareness and research on the structures of the posterolateral corner of the knee, particularly the FCL. Studying the detailed structure of the FCL may provide a better understanding that can lead to better diagnosis and treatments following injury. Therefore, this article reviews the FCL, which appears to be the primary restraint to varus rotation but is poorly oriented to resist external rotation of the knee.

Screw loosening and iliotibial band friction after posterolateral corner reconstruction

BACKGROUND

Many reconstruction techniques have already been developed for treating posterolateral corner (PLC) injuries, with still no consensus regarding what would be the best option. Some techniques use non-bone tunnel fixation, attaching the graft to the femur using a cortical screw with toothed washer. The main objective of the present study is to evaluate complications related to fixation performed by a screw and toothed washer technique.

METHODS

A prospective study with surgical reconstruction of the PLC structures of the knee between January 2008 and December 2009 was performed. PLC reconstruction included reconstruction of the lateral collateral ligament, popliteofibular ligament and popliteal muscle tendon. Fixation of the grafts in the femur was achieved by means of a 4.5mm screw with a toothed washer. The assessments were done using the following methods: objective IKDC, subjective IKDC, Lysholm and Tegner. Radiographic evaluations were performed immediately after the operation, at 3, 6 and 12months after surgery, and yearly thereafter. Complications were documented.

RESULTS

The mean subjective IKDC score after the operation was 69.2; Lysholm scale was 80.7. Two patients presented failure of reconstructions of the PLC. In the radiographic evaluations, signs of loosening of the screw with toothed washer in the femur were observed in eight cases (66.6%). Six patients (50%) complained of lateral pain after the operation.

CONCLUSION

The technique of femoral fixation was shown to be efficient in restoration of stability. However there was a high rate of complications secondary to implant, such as loosening of the screws and iliotibial tract friction.

LEVEL OF EVIDENCE

Case series, leve IV.

Improving outcomes for posterolateral knee injuries

Until recently, the posterolateral corner of the knee was noted both for its complex anatomy and diagnostic challenges. To improve the understanding of the posterolateral knee, we completed a comprehensive and stepwise research program with a focus on five primary areas: (1) surgical approach and relevant anatomy; (2) diagnosis; (3) clinically relevant biomechanics; (4) natural history; and (5) surgical treatment. Based on this comprehensive research program, the diagnosis and outcomes following treatment of posterolateral knee injuries have been significantly improved comparing the preoperative state to the state of the knee at a minimum 2 year follow-up in the cases series presented here. © 2014 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 32:485-491, 2014.

Anatomic, arthroscopically assisted, mini-open fibular collateral ligament reconstruction: an in vitro biomechanical study

BACKGROUND

The fibular collateral ligament (FCL) is the primary restraint to varus rotation of the knee joint. Arthroscopic techniques are widely used and minimally invasive, but anatomic arthroscopic reconstruction of an isolated FCL injury has not been reported.

HYPOTHESIS

Anatomic reconstruction of an isolated FCL injury can be performed arthroscopically and will restore the knee to near-normal stability.

STUDY DESIGN

Controlled laboratory study.

METHODS

A total of 12 nonpaired, fresh-frozen cadaveric knees were biomechanically subjected to a 10-N·m varus moment and 5-N·m external and internal rotation torques at 0°, 15°, 30°, 60°, 90°, and 120° of knee flexion, respectively (0° only for varus loading). Testing was performed with an intact and sectioned FCL and also after an anatomic reconstruction of the FCL by arthroscopic technique. Kinematics of each knee under various loading conditions was determined with a robotic universal force/moment sensor testing system.

RESULTS

After sectioning, significant increases were found in varus rotation at 0°, 15°, 30°, 60°, 90°, and 120° of knee flexion; in external rotation at 15°, 30°, and 60° of knee flexion; and in internal rotation at 30°, 60°, and 90° of knee flexion. After reconstruction, full recovery of knee stability was observed in varus rotation at 0°, 15°, 30°, and 60°; in external rotation at 0°, 15°, 30°, 60°, 90°, and 120°; and in internal rotation at 0°, 15°, 30°, 60°, 90°, and 120°. When the sectioned and intact FCL knee conditions were compared, significant increases of 3.4° at 90° of flexion and 3.4° at 120° of flexion were found (P < .001, both conditions); when the reconstructed and sectioned FCL knee conditions were compared, significant decreases of 1.7° at 90° of flexion and 1.7° at 120° of knee flexion were found (P = .033 and .043, respectively).

CONCLUSION

An anatomic reconstruction of the FCL can be performed by an arthroscopically assisted mini-open technique with an isolated FCL injury, and near-normal stability of the knee can be restored.

CLINICAL RELEVANCE

Anatomic reconstruction of the FCL by an arthroscopically assisted mini-open technique is a viable, less invasive option to treat nonrepairable isolated FCL injury.