Paediatric ACL repair reinforced with temporary internal bracing

Purpose

Instability following non-operative treatment of anterior cruciate ligament (ACL) rupture in young children frequently results in secondary chondral and/or meniscal injuries. Therefore, many contemporary surgeons advocate ACL reconstruction in these patients, despite the challenges posed by peri-articular physes and the high early failure rate. We report a novel management approach, comprising direct ACL repair reinforced by a temporary internal brace in three children.

Methods

Two patients (aged 5 and 6 years) with complete proximal ACL ruptures and a third (aged seven) with an associated tibial spine avulsion underwent direct surgical repair, supplemented with an internal brace that was removed after 3 months.

Results

Second-look arthroscopy, examination and imaging at 3 months confirmed knee stability and complete ACL healing in all cases. Normal activities were resumed at 4 months, and excellent objective measures of function, without limb growth disturbance, were noted beyond 2 years.

Conclusion

ACL repair in young children using this technique negates the requirement and potential morbidity of graft harvest and demonstrates the potential for excellent outcome as an attractive alternative to ACL reconstruction, where an adequate ACL remnant permits direct repair.

Level of evidence

IV.

     

The correlation between anterior cruciate ligament injury in elite alpine skiers and their parents

Purpose

The aim of this study was to investigate whether a familiar correlation with anterior cruciate ligament (ACL) injury exists between competitive alpine skiers and their parents.

Methods

All 593 (293 males, 300 females) elite alpine skiers who have studied at a Swedish alpine Ski High School during 2006 and 2012 answered a questionnaire whether they or their parents had suffered an ACL injury. A total of 418 skiers (70 %) answered the questionnaire.

Results

Twenty-nine per cent (n = 19) out of the 65 ACL-injured skiers reported that they had a parent (mother or father) who have had an ACL injury. In skiers without an ACL injury (n = 353), the result was 18 % (n = 64). An odds ratio of 1.95 (95 % confidence interval 1.04–3.65) was found to suffer an ACL injury if you have a parent who has had an ACL injury compared with if you have a parent without any ACL injury.

Conclusion

The findings of the current study demonstrated a family history to tear the ACL between alpine skiers who had studied at a Swedish Ski High School and ACL injuries of their parents.

Level of evidence

III.

     

Complications after epiphyseal reconstruction of the anterior cruciate ligament in prepubescent children

Purpose

Reconstruction of the anterior cruciate ligament (ACL) remains a major concern in the prepubescent, skeletally immature patient with wide open growth plates. Different surgical techniques have been proposed. This study reports the results and complications of ACL reconstruction in young children using an all epiphyseal technique.

Methods

Between 2006 and 2010, 12 patients (10–13 years, median 12.1 years) underwent epiphyseal primary ACL reconstruction, with a total of 13 knee procedures. Patients were assessed retrospectively with a median follow-up of 54 months (range 39–80 months) consisting of a clinical examination, instrumented arthrometer testing and radiological analysis. Functional status was assessed using the Lysholm knee score, Tegner activity scale and IKDC-2000 form.

Results

According to the IKDC examination form, five knees were rated as normal, six near normal and two abnormal. The median IKDC score at follow-up was 88.5 points (range 75–99 points). The mean side–to-side difference in KT-1000 ligament laxity testing was 1.5 mm (±2.5 mm). In two patients, reoperation was necessary due to graft failure. Two patients developed significant leg length inequality; one with 20 mm overgrowth and varus malalignment after re-reconstruction and the second developed arthrofibrosis and overgrowth of 16 mm. Four patients had minor limb length discrepancy ranging between +5 and +10 mm; no growth arrest was noted. One patient with an intact but slightly elongated graft required a meniscal suture 34 months after ACL reconstruction following a traumatic medial meniscal lesion.

Conclusion

Despite using the epiphyseal technique in ACL reconstruction, relevant growth discrepancy can occur. Thereby, overgrowth rates appear to potentially pose a major clinical problem, which has remained unreported so far. Overall, there is a considerable high risk of complications in this patient group.

Level of evidence

IV.

     

No infections in 1300 anterior cruciate ligament reconstructions with vancomycin pre-soaking of hamstring grafts

Purpose

To investigate the pre-soaking of hamstring grafts in topical vancomycin, in addition to IV prophylaxis, during anterior cruciate ligament (ACL) reconstruction to reduce the incidence of post-operative infection, and to describe an evidence-based diagnostic and treatment algorithm to facilitate early diagnosis and appropriate management of possible knee sepsis post-operatively after ACL reconstruction.

Methods

This study is a controlled observational series comprising of 1585 individuals who underwent ACL reconstruction over a 13-year period. All surgeries were performed by a single surgeon at the same hospital. Group 1 consisted of 285 patients who received pre-operative IV antibiotics without topical graft pre-soaking. Group 2 consisted of 1300 individuals who received IV antibiotics and graft pre-soaking in a vancomycin solution of 5 mg/mL.

Results

In group 1, a total of four patients suffered a post-operative joint infection (1.4 %). Three out of the four were culture positive for Staphylococcus species. The fourth was culture negative but was managed as an acute infection. Group 2 suffered no post-operative infections (0 %). Statistical analysis of the vancomycin pre-soak with IV antibiotics group, compared with IV antibiotics-alone group, revealed a significantly reduced post-operative infection rate using a Fisher’s exact test (P = 0.0011) and Chi-square test with Yates’ correction (P = 0.0003).

Conclusions

Pre-soaking of hamstrings grafts with topical vancomycin reduced the rate of post-operative infection when compared to IV antibiotics alone. This technique should be utilised by surgeons to reduce the overall incidence of knee sepsis post-ACL reconstruction.

Level of evidence

III.

     

Does notch size predict ACL insertion site size?

Purpose

The primary purpose of the current study is to identify a possible correlation between the femoral intercondylar notch size and the ACL insertion site size. The secondary purpose is to determine if there is a difference between male and female notch widths and insertion site sizes.

Methods

For this study, 82 patients (41 men and 41 women) with an average age of 24.1 ± 10.0 years (range 13–58 years) undergoing anterior cruciate ligament (ACL) reconstruction were included. Arthroscopic measurements were taken at the base, middle, and top of the notch. Additionally, the notch height was measured at the highest point. The insertion sites of the ACL were identified, marked using electrocautery, and measured. The correlation between notch width and ACL insertion site size was calculated. In addition, differences between men and women with regard to the notch width and ACL insertion site size were determined.

Results

Significant positive correlations were found between the notch widths and ACL insertion site measurements and ranged from 0.222 to 0.379 (P < 0.05). There were significant differences between men and women with regard to notch and insertion site size.

Conclusion

The results of this study show that there is a significant, but weak correlation between the notch width and the ACL insertion site size. Women had a smaller notch and a smaller insertion site than men. This knowledge could influence pre-operative decision-making with regard to graft choice, single- or double-bundle surgery, and graft size.

Level of evidence

Case series, Level IV.

     

Dynamic and static tibial translation in patients with anterior cruciate ligament deficiency initially treated with a structured rehabilitation protocol

Purpose

To compare dynamic and static tibial translation, in patients with anterior cruciate ligament deficiency, at 2- to 5-year follow-up, with the tibial translation after 4 months of rehabilitation initiated early after the injury. Secondarily, to compare tibial translation in the injured knee and non-injured knee and explore correlations between dynamic and static tibial translation.

Methods

Twelve patients with ACL rupture were assessed at 3–8 weeks after ACL injury, after 4 months of structured rehabilitation, and 2–5 years after ACL injury. Sagittal tibial translation was measured during the Lachman test (static translation) and during gait (dynamic translation) using a CA-4000 electrogoniometer.

Results

Static tibial translation was increased bilateral 2–5 years after ACL injury, whereas the dynamic tibial translation was unchanged. Tibial translation was greater in the injured knee compared with the non-injured knee (Lachman test 134 N 9.1 ± 1.0 vs. 7.0 ± 1.7 mm, P = 0.001, gait 5.6 ± 2.1 vs. 4.7 ± 1.8 mm, P = 0.011). There were no correlations between dynamic and static tibial translation.

Conclusion

Dynamic tibial translation was unchanged in spite of increased static tibial translation in the ACL-deficient knee at 2- to 5-year follow-up compared to directly after rehabilitation. Dynamic tibial translation did not correlate with the static tibial translation. A more normal gait kinematics may be maintained from completion of a rehabilitation programme to mid-term follow-up in patients with ACL deficiency treated with rehabilitation only.

Level of evidence

IV.

     

Anterolateral ligament abnormalities in patients with acute anterior cruciate ligament rupture are associated with lateral meniscal and osseous injuries

Objective

To determine the frequency of anterolateral ligament (ALL) injury in patients with acute anterior cruciate ligament (ACL) rupture and to analyse its associated injury patterns.

Methods

Ninety patients with acute ACL rupture for which MRI was obtained within 8 weeks after the initial trauma were retrospectively identified. Two radiologists assessed the status of the ALL on MRI by consensus. The presence or absence of an ALL abnormality was compared with the existence of medial and lateral meniscal tears diagnosed during arthroscopy. Associated collateral ligament and osseous injuries were documented with MRI.

Results

Forty-one of 90 knees (46 %) demonstrated ALL abnormalities on MRI. Of 49 knees with intact ALL, 15 (31 %) had a torn lateral meniscus as compared to 25 torn lateral menisci in 41 knees (61 %) with abnormal ALL (p?=?0.008). Collateral ligament (p?≤?0.05) and osseous injuries (p?=?0.0037) were more frequent and severe in ALL-injured as compared with ALL-intact knees.

Conclusion

ALL injuries are fairly common in patients with acute ACL rupture and are statistically significantly associated with lateral meniscal, collateral ligament and osseous injuries.

Key Points

? ALL injuries are fairly common in patients with acute ACL rupture. ? ALL injuries are highly associated with lateral meniscal and osseous injuries. ? MRI assessment of ACL-injured knees should include evaluation of the ALL.

     

Anterior cruciate ligament tibial insertion site is elliptical or triangular shaped in healthy young adults: high-resolution 3-T MRI analysis

Purpose

To clarify the morphology of anterior cruciate ligament (ACL) tibial insertion site in healthy young knees using high-resolution 3-T MRI.

Methods

Subjects were 50 ACL-reconstructed patients with a mean age of 21.4 ± 6.8 years. The contralateral healthy knees were scanned using high-resolution 3-T MRI. The tibial insertion sites of the anteromedial (AM) and posterolateral (PL) bundle fibres, and the ACL attachment on the anterior horn of lateral meniscus (AHLM) were segmented from the MR images, and 3D models were reconstructed to evaluate the morphology. The shape of ACL footprint was qualitatively analysed, and the size of AM and PL attachments and AHLM overlapped area was measured digitally.

Results

Tibial AM and PL bundles were clearly identified in 42 of 50 knees (84.0%). Morphology of the whole ACL tibial insertion site was elliptical in 23 knees (54.8%) and triangular in 19 knees (45.2%), but not classified as C-shape in any knees. However, the AM bundle attachment was of C-shape in 29 knees (69.0%) and band-like in 13 knees (31.0%). Overlap of ACL on AHLM was found in 26 knees (61.9%), and the size of the overlapped area was 4.8 ± 4.7% of the whole ACL insertion site.

Conclusion

3D morphology of the intact ACL tibial insertion site analysed by high-resolution 3-T MRI was elliptical or triangular in healthy young knees. However, the AM bundle insertion site was of C-shape or band-like. A small lateral portion of the ACL was overlapped with the AHLM. As for clinical relevance, these findings should be considered in order to reproduce the native ACL insertion site sufficiently.

Level of evidence

III.

     

Increased odds of patient-reported success at 2 years after anterior cruciate ligament reconstruction in patients without cartilage lesions: a cohort study from the Swedish National Knee Ligament Register

Purpose

To investigate whether the surgical technique of single-bundle anterior cruciate ligament (ACL) reconstruction, the visualization of anatomic surgical factors and the presence or absence of concomitant injuries at primary ACL reconstruction are able to predict patient-reported success and failure. The hypothesis of this study was that anatomic single-bundle surgical procedures would be predictive of patient-reported success.

Methods

This cohort study was based on data from the Swedish National Knee Ligament Register during the period of 1 January 2005 through 31 December 2014. Patients who underwent primary single-bundle ACL reconstruction with hamstring tendons were included. Details on surgical technique were collected using an online questionnaire comprising essential anatomic anterior cruciate ligament reconstruction scoring checklist items, defined as the utilization of accessory medial portal drilling, anatomic tunnel placement, the visualization of insertion sites and pertinent landmarks. A univariate logistic regression model adjusted for age and gender was used to determine predictors of patient-reported success and failure, i.e. 20th and 80th percentile, respectively, in the Knee injury and Osteoarthritis Outcome Score (KOOS), 2 years after ACL reconstruction.

Results

In the 6889 included patients, the surgical technique used for single-bundle ACL reconstruction did not predict the predefined patient-reported success or patient-reported failure in the KOOS₄. Patient-reported success was predicted by the absence of concomitant injury to the meniscus (OR = 0.81 [95% CI, 0.72–0.92], p = 0.001) and articular cartilage (OR = 0.70 [95% CI, 0.61–0.81], p < 0.001). Patient-reported failure was predicted by the presence of a concomitant injury to the articular cartilage (OR = 1.27 [95% CI, 1.11–1.44], p < 0.001).

Conclusion

Surgical techniques used in primary single-bundle ACL reconstruction did not predict the KOOS 2 years after the reconstruction. However, the absence of concomitant injuries at index surgery predicted patient-reported success in the KOOS. The results provide further evidence that concomitant injuries at ACL reconstruction affect subjective knee function and a detailed knowledge of the treatment of these concomitant injuries is needed.

Level of evidence

Retrospective cohort study, Level III.

     

No negative effect on patient-reported outcome of concomitant cartilage lesions 5–9 years after ACL reconstruction

Purpose

To compare patient-reported outcome 5–9 years after anterior cruciate ligament (ACL) reconstruction in patients with and without a concomitant full-thickness [International Cartilage Repair Society (ICRS) grade 3–4] cartilage lesion.

Methods

This is a prospective follow-up of a cohort of 89 patients that were identified in the Norwegian National Knee Ligament Registry and included in the current study in 2007, consisting of 30 primary ACL-reconstructed patients with a concomitant, isolated full-thickness cartilage lesion (ICRS grade 3 and 4) and 59 matched controls without cartilage lesions (ICRS grade 1–4). At a median follow-up of 6.3 years (range 4.9–9.1) after ACL reconstruction, 74 (84 %) patients completed the Knee Injury and Osteoarthritis Outcome Score (KOOS), which was used as the main outcome measure. Secondary outcomes included radiographic evaluation according to the Kellgren–Lawrence criteria of knee osteoarthritis (OA).

Results

At follow-up, 5–9 years after ACL reconstruction, no statistically significant differences in KOOS were detected between patients with a concomitant full-thickness cartilage lesion and patients without concomitant cartilage lesions. Radiographic knee OA of the affected knee, defined as Kellgren and Lawrence ≥2, was significantly more frequent in subjects without a concomitant cartilage lesion (p = 0.016).

Conclusion

ACL reconstruction performed in patients with an isolated concomitant full-thickness cartilage lesion restored patient-reported knee function to the same level as ACL reconstruction performed in patients without concomitant cartilage lesions, 5–9 years after surgery. This should be considered in the preoperative information given to patients with such combined injuries, in terms of the expected outcome after ACL reconstruction and in the counselling and decision-making on the subject of surgical treatment of the concomitant cartilage lesion.

Level of evidence

Prognostic; prospective cohort study, Level I.

     

Satisfactory outcomes following combined unicompartmental knee replacement and anterior cruciate ligament reconstruction

Purpose

There exist limited options for treatment of patients with combined medial compartment arthritis and anterior cruciate ligament (ACL) deficiency. Ideal treatment is one that offers lasting relief of symptoms not compromising any future surgery. Unicompartmental knee replacement has shown consistently good results in the relatively young and active population, but there is a high reported incidence of failure up to 20%, if performed in ACL-deficient knees. One of the recognized treatment modality is combined ACL reconstruction and unicompartmental arthroplasty. A systematic review was conducted looking at the demographics, techniques, complications and outcome of combined ACL reconstruction with unicompartmental knee arthroplasty.

Methods

A systematic literature search within the online Medline, PubMed Database, EMBASE, Web of Science, Cochrane and Google Scholar was carried out until October 2016 to identify relevant articles. A study was defined eligible if it met the following inclusion criteria: the surgical procedure combined unicompartmental knee arthroplasty and anterior cruciate ligament reconstruction; patient’s clinical and/or functional outcomes were reported; any complications intra-operatively and post-operatively were reported; and the full-text articles, written in English, German, Italian, Dutch or Spanish, were available. Quality and risk of bias assessments were done using standardized criteria set.

Results

A total of 8 studies met the inclusion criteria encompassing 186 patients who were treated with simultaneous ACL reconstruction and unicompartmental knee arthroplasty. The mean age was 50.5 years (range from 44 to 56) with a mean follow-up of 37.6 months (range from 24 to 60). There was an improvement in mean Oxford Score from 27.5 to 36.8. Complications reported included tibial inlay dislocation (n = 3), conversion to a total knee arthroplasty (n = 1), infection requiring two-stage revision (n = 2), deep-vein thrombosis (n = 1), stiffness requiring manipulation under anaesthesia (n = 1), retropatellar pain requiring arthroscopic adhesiolysis (n = 1).

Conclusion

Unicompartmental knee arthroplasty combined with ACL reconstruction can be a valid treatment option for selected patients, with combined medial unicompartmental knee osteoarthritis and ACL deficiency.

Level of evidence

Systematic Review of Level IV Studies, Level IV.

     

Autograft soaking in vancomycin reduces the risk of infection after anterior cruciate ligament reconstruction

Purpose

To determine whether the bathing of an anterior cruciate ligament (ACL) autograft in vancomycin reduces the rate of infection following an ACL reconstruction.

Methods

Retrospective analysis of all ACL reconstructions over an 8-year period in two University Hospitals. In the initial 4-year period, all patients were operated on under classical antibiotic intravenous prophylaxis (group 1). Over the last 4-year period, this prophylaxis was supplemented with presoaking of the autograft (group 2). Presoaking was performed with sterile gauze previously saturated with a vancomycin solution (5 mg/ml).

Results

There were 810 and 734 patients in group 1 and 2, respectively. Fifteen cases of knee joint infections were identified in the series (0.97 %). All of these infections occurred in group 1, representing a rate of infection of 1.85 % in comparison with 0 % in group 2 (p < 0.001).

Conclusions

Autograft presoaking with vancomycin in combination with classical intravenous antibiotic prophylaxis reduced the rate of knee joint infection following an ACLR in comparison with antibiotic prophylaxis alone. This technique could be of relevance in daily clinical practice to prevent infection after ACLR.

Level of evidence

Case control study, retrospective comparative study, Level III.

     

Optimal entry position on the lateral femoral surface for outside-in drilling technique to restore the anatomical footprint of anterior cruciate ligament

Purpose

To investigate the optimal starting points for drilling on the lateral femoral condyle for better coverage of the anatomical footprint of the anterior cruciate ligament (ACL) using the outside-in (OI) technique in a single-bundle ACL reconstruction.

Methods

Femoral tunnel drilling was simulated on three-dimensional bone models from 40 subjects by connecting the centre of the ACL footprint with various points on the lateral femoral surface. The percentage of the femoral footprint covered by apertures of the virtual tunnel sockets with 9 mm diameter was calculated for each tunnel.

Results

The mean percentages of the femoral footprint covered by the apertures of the virtual tunnel sockets were significantly higher when drilled at 2 and 3 cm from the lateral epicondyle on a 45° line and a 60° line anterior from the proximal–distal axis than the other points. However, articular cartilage damage was occurred in nine subjects at 3 cm on a 60° line and eight subjects at 3 cm on a 45° line. Posterior wall blowout occurred in five subjects at 3 cm on a 45° line. Thus, OI drilling at 3 cm from the epicondyle has a risk of these complications.

Conclusion

During the OI drilling of the femoral tunnel, connecting the centre of the anatomical footprint of the ACL and the entry drilling point at 2 cm from the lateral epicondyle on between the 45° line and the 60° line anterior from the proximal–distal axis provides an oval-shaped socket aperture that covers and restores the native ACL footprint as nearly as possible.

Level of evidence

III.

     

A new simulator model for knee arthroscopy procedures

Purpose

Arthroscopy is currently the “gold standard” for various surgeries performed on the knee joint. Therefore, surgeons wishing to operate in this professional field should be able to perform this technique. Arthroscopic training, an experimental laboratory, is important for the surgeons’ training, enabling them to increase their skills with the specific instruments and to become familiar with the operating techniques. The aim of this study was to present a new surgical simulator for training in arthroscopic procedures of the knee.

Methods

The Kneetrainer 1 is a simulator consisting of a type of thermo-retractile, thermo-sensitive synthetic rubber that has texture, colour, consistency, and mechanical resistance that mimic many human tissues. Nine simulators were used, operated by seventeen expert Brazilian surgeons in knee surgery. The surgeons performed arthroscopy, meniscectomy, and reconstruction of the anterior cruciate ligament (ACL), responded to an electronic questionnaire with several variables, and gave an overall score on the ability of the device to perform realistic simulation for the above procedures.

Results

The ability to perform the procedures of meniscectomy and ACL reconstruction was considered adequate by 82 and 100 % of the specialists, respectively. The overall scores for the ability to perform realistic simulation for the procedures meniscectomy and reconstruction of the anterior cruciate ligament by arthroscopy were 64.7 and 82.4 %, respectively. The simulator was therefore considered suitable for practical application with novice surgeons.

Conclusion

The Kneetrainer 1 simulator was assessed as an effective tool for recreating accurate arthroscopic knee procedures. In addition, the simulator may be effective as a means of honing the skills of novice surgeons. Future investigations should be performed to validate the reliability of the simulator.

Level of evidence

IV.

     

Arthroscopic all-inside ramp lesion repair using the posterolateral transseptal portal view

Purpose

The purpose of this study was to evaluate and describe the clinical results and outcomes of a novel method for all-inside suture repair of medial meniscus ramp lesions through posteromedial and posterolateral transseptal portals during anterior cruciate ligament (ACL) reconstruction. Further, this investigation compared the posterolateral view to the notch view for diagnosis and repair.

Methods

Between 2011 and 2014, 166 patients had ramp lesions concomitantly with ACL injury; 128 patients (107 men and 21 women) were enrolled in the study after qualification. All patients underwent repair of the posterior horn ramp lesion of the medial meniscus, using a suture hook device with PDS No. 1 through a posteromedial portal while viewing from the posterolateral transseptal portal during ACL reconstruction, with a minimum of a 2-year follow-up.

Results

Patients were followed up for a minimum of 2 years (range 24–47 months). Their average Lysholm score increased from 61.7 ± 3.2 preoperatively to 87.8 ± 3.9 at last follow-up (p < 0.001). Moreover, their average IKDC scores also improved from 53.6 ± 2.1 (pre-op) to 82.1 ± 3.5 (at last follow-up) (p < 0.001). The peroneal nerve and the popliteal neurovascular bundle were not damaged in any of the patients.

Conclusion

This study provides evidence that the posterolateral transseptal technique protects neurovascular structures. This technique may be used safely and easily for repair of the posterior horn ramp lesion of the medial meniscus during ACL reconstruction.

Level of evidence

IV.

     

Characteristics of inpatient anterior cruciate ligament reconstructions and concomitant injuries

Purpose

The purpose of this epidemiologic study was to quantify the incidence, expense, and concomitant injuries for anterior cruciate ligament reconstruction (ACLR) procedures in the USA from 2003 to 2011 that required an inpatient stay. It was hypothesized that the relative reported rates of concomitant knee injuries would be greater with the MCL and menisci compared to all other concomitant knee injuries.

Methods

The National Inpatient Sample from 2003 to 2011 was retrospectively sampled using ICD-9-CM codes to identify ACLR patients and to extrapolate national averages.

Results

Between the years of 2003–2011, an average of 9,037 ± 1,728 inpatient hospitalization included ACLRs, of which 4,252 ± 1,824 were primarily due to the ACLR. Inpatient visits primarily due to ACLR involved an average hospitalization of 1.7 ± 0.2 days and cost $30,118 ± 9,066 per patient. Knee injuries that were commonly reported along with inpatient ACLRs included medial meniscus damage (18.1 %), lateral meniscus damage (16.8 %), collateral ligament repairs (12.3 %), and medial collateral ligament strains (6.9 %). Prevalence of meniscus injuries was consistent across years, but MCL-related injuries increased over time.

Conclusions

ACLR-related inpatient hospitalizations account for approximately 7.1 % of the total ACLRs performed annually in the USA. Inpatient ACLR procedures continue to decrease in frequency; however, the mean cost per patient increased. Meniscus and collateral ligament injuries were the most commonly reported concomitant knee injuries. The clinical relevance of this investigation is that it informs, on a large clinical cohort of patients, the current state of incidence and expense for ACLR surgeries in an inpatient setting.

Level of evidence

Prognostic, retrospective study, Level II.

     

Quantitative magnetic resonance imaging (MRI) morphological analysis of knee cartilage in healthy and anterior cruciate ligament-injured knees

Purpose

To analyze the morphological change in the cartilage of the knee after anterior cruciate ligament (ACL) injury by comparing with that of the intact contralateral knee.

Methods

A total of 22 participants (12 male and 10 female patients) who had unilateral ACL injury underwent MRI scan of both the injured and intact contralateral knees. Sagittal plane images were segmented using a modeling software to determine cartilage volume and cartilage thickness in each part of the knee cartilage that were compared between the ACL-injured and the intact contralateral knees. Furthermore, the male and female patients’ data were analyzed in subgroups.

Results

The ACL-injured knees had statistically significant lower total knee cartilage volume than the intact contralateral knees (P = 0.0020), but had similar mean thickness of total knee cartilage (not significant: n.s.). In the male subgroup, there was no significant difference in cartilage volume and thickness between normal and ACL-injured knees. In the female subgroup, the ACL-injured knees demonstrated statistically significant difference in total knee cartilage volume (P = 0.0004) and thickness (P = 0.0024) compared with the normal knees. The percentage change in the cartilage thickness in women was significantly greater than that in men.

Conclusion

Cartilage volume was significantly smaller in the ACL-injured knees than in the contralateral intact knees in this cohort. Women tended to display greater cartilage volume and thickness change after ACL injury than men. These findings indicated that women might be more susceptible to cartilage alteration after ACL injuries.

Level of evidence

III.

     

Radiographic femoral bicondylar width predicts anterior cruciate ligament insertion site sizes

Purpose

The purpose of this study was to determine whether radiographic femoral bicondylar width predicts intra-operative anterior cruciate ligament (ACL) insertion site sizes.

Methods

Seventy-three consecutive patients (39 males and 34 females; mean age 25.2 years ± 10.2) who underwent anatomic ACL reconstruction were retrospectively reviewed. Femoral condyle width was measured using a pre-operative anteroposterior (AP) radiograph of the operative knee. Lines were drawn through the anatomic axis of the femur, as well as perpendicularly through the condyles. Bicondylar width was measured as the maximum width across both the medial and lateral femoral condyles utilizing this perpendicular line. The ACL insertion site lengths (in the AP direction) of both the tibia and the femur were measured intra-operatively using a commercially available arthroscopic ruler.

Results

The average bicondylar width was significantly smaller for females compared to males (p < 0.05). The average tibial and femoral insertion site sizes were significantly smaller for females compared to males (p < 0.05). Regression analysis predicted tibial (r ² = 0.88) and femoral (r ² = 0.90) insertion site sizes based on femoral bicondylar width measurements.

Conclusion

A simple radiographic measurement of femoral bicondylar width can predict intra-operative tibial and femoral insertion site sizes, which has the potential to assist surgeons in performing individualized ACL reconstruction in cases where MRI scan is unavailable.

Level of evidence

IV.

     

Lateral displacement,sulcus angle and trochlear angle are associated with early patellofemoral osteoarthritis following anterior cruciate ligament reconstruction

Purpose

Patellofemoral osteoarthritis (PFOA) occurs in approximately half of anterior cruciate ligament (ACL)-injured knees within 10–15 years of trauma. Risk factors for post-traumatic PFOA are poorly understood. Patellofemoral alignment and trochlear morphology may be associated with PFOA following ACL reconstruction (ACLR), and understanding these relationships, particularly early in the post-surgical time period, may guide effective early intervention strategies. In this study, patellofemoral alignment and trochlear morphology were investigated in relation to radiographic features of early PFOA 1-year post-ACLR.

Methods

Participants (aged 18–50 years) had undergone ACLR approximately 1 year prior to being assessed. Early PFOA was defined as presence of a definite patellofemoral osteophyte on lateral or skyline radiograph. Sagittal and axial plane alignment and trochlear morphology were estimated using MRI. Using logistic regression, the relationship between alignment or morphology and presence of osteophytes was evaluated.

Results

Of 111 participants [age 30 ± 8.5; 41 (37%) women], 19 (17%) had definite osteophytes, only two of whom had had patellofemoral chondral lesions noted intra-operatively. One measure of patellar alignment (bisect offset OR 1.1 [95% confidence interval 1.0, 1.2]) and two measures of trochlear morphology (sulcus angle OR 1.1 [1.0, 1.2], trochlear angle OR 1.2 [1.0, 1.5]) were associated with patellofemoral osteophytes.

Conclusions

Patellofemoral malalignment and/or altered trochlear morphology were associated with PFOA 1 year following ACLR compared to individuals post-ACLR without these features. Clarifying the role of alignment and morphology in post-traumatic PFOA may contribute to improving early intervention strategies aimed at secondary prevention.

Level of evidence

IV.