ACL–PCL and intercondylar notch impingement: magnetic resonance imaging of native and double-bundle ACL-reconstructed knees

Purpose

The purpose of this study was to: (1) define the relationship between the ACL and PCL in normal knees; (2) determine whether ACL–PCL impingement occurs in native knees; and (3) determine whether there is a difference in impingement between double-bundle reconstructed and native knees.

Methods

Eight subjects were identified (age 20–50; 6 females, 2 males). All were at least 1-year status postanatomic double-bundle ACL reconstruction (allograft; AM = 8 mm; PL = 7 mm) and had no history of injury or surgery to the contralateral knee. MRIs of both knees were performed with the knee at 0 and 30° of flexion. The images were evaluated by a non-treating surgeon and two musculoskeletal radiologists. Coronal and sagittal angles of AM and PL bundles, Liu’s PCL index and the distance between ACL and PCL on modified axial oblique images were recorded. Impingement was graded (1) no contact; (2) contact without deformation; or (3) contact and distortion of PCL contour.

Results

Seventy-five percent (6) of the native ACL’s showed no contact with the roof of the intercondylar notch or PCL, compared to 25 % (2) of the double-bundle reconstructed ACLs. One double-bundle reconstructed ACL showed intercondylar notch roof and ACL–PCL impingement (12.5 %). Significant differences were found between the native ACL and the double-bundle reconstructed ACL for the coronal angle of the AM (79° vs. 72°, p = 0.002) and PL bundle (75° vs. 58°, p = 0.001). No differences in ROM or stability were noted at any follow-up interval between groups based on MRI impingement grade.

Conclusion

ACL–PCL contact occurred in 25 % of native knees. Contact between the ACL graft and PCL occurred in 75 % of double-bundle reconstructed knees. ACL–PCL impingement, both contact and distortion of the PCL, occurred in one knee after double-bundle reconstruction. This study offers perspective on what can be considered normal contact between the ACL and PCL and how impingement after ACL reconstruction can be detected on MRI.

Level of evidence

Cohort Study, Level III.     

Comparison of double-bundle anterior cruciate ligament (ACL) reconstruction and single-bundle reconstruction with remnant pull-out suture

Purpose

The purpose of this study was to evaluate the stability and functional outcomes of anterior cruciate ligament (ACL) reconstruction by tensioning of the ACL remnant using pull-out sutures compared with ACL double-bundle reconstruction.

Methods

Forty-four patients were included in single-bundle reconstruction with remnant tensioning group (Group 1), and 56 patients were included in the double-bundle reconstruction group (Group 2). The remnant tissue was tensioned to the direction of posterolateral bundle, which unrelated to the type of remnant bundle. Objective knee stability was evaluated by anterior stress radiography, KT-1000 and lateral pivot shift tests. The Tegner activity scale, International Knee Documentation Committee and OrthopädischeArbeitsgruppeKnie scoring systems were used for clinical evaluation.

Results

No statistically significant intergroup differences were observed in mechanical stability and clinical results (n.s). However, surgical time of remnant tensioning group is shorter than double-bundle reconstruction group (P = 0.005).

Conclusion

Remnant tensioning suture with single-bundle reconstruction could be used with positive results as good as double-bundle technique if a good ACL remnant was found bridging the femur and tibia, rather than debride or damage to the remnant tissue during operation.

Level of evidence

Retrospective, comparative cohort study, Level IV.     

Anatomic single- versus double-bundle ACL reconstruction: a meta-analysis

Purpose

To determine whether anatomic double-bundle anterior cruciate ligament (ACL) reconstruction compared to anatomic single-bundle ACL reconstruction more effectively restored antero–posterior (A–P) laxity, rotatory laxity and reduced frequency of graft rupture. Our hypothesis was that anatomic double-bundle ACL reconstruction results in superior rotational knee laxity and fewer graft ruptures due to its double-bundle tension pattern, compared with anatomic single-bundle ACL reconstruction.

Methods

An electronic search was performed using the PubMed, EMBASE and Cochrane Library databases. All therapeutic trials written in English reporting knee kinematic outcomes and graft rupture rates of primary anatomic double- versus single-bundle ACL reconstruction were included. Only clinical studies of levels I–II evidence were included. Data regarding kinematic tests were extracted and included pivot-shift test, Lachman test, anterior drawer test, KT-1000 measurements, A–P laxity measures using navigation and total internal–external (IRER) laxity measured using navigation, as well as graft failure frequency.

Results

A total of 7,154 studies were identified of which 15 papers (8 randomized controlled trials and 7 prospective cohort studies, n = 970 patients) met the eligibility criteria. Anatomic ACL double-bundle reconstruction demonstrated less anterior laxity using KT-1000 arthrometer with a standard mean difference (SMD) = 0.36 (95 % CI 0.214–0.513, p < 0.001) and less A–P laxity measured with navigation (SMD = 0.29 95 % CI 0.01–0.565, p = 0.042). Anatomic double-bundle ACL reconstruction did not lead to significant improvements in pivot-shift test, Lachman test, anterior drawer test, total IRER or graft failure rates compared to anatomic single-bundle ACL reconstruction.

Conclusion

Anatomic double-bundle ACL reconstruction is superior to anatomic single-bundle reconstruction in terms of restoration of knee kinematics, primarily A–P laxity. Whether these improvements of laxity result in long-term improvement of clinical meaningful outcomes remains uncertain.

Level of evidence

II.     

The effect of notchplasty in anterior cruciate ligament reconstruction: a biomechanical study in the porcine knee

Introduction

Notchplasty is frequently performed by many orthopaedic surgeons during anterior cruciate ligament (ACL) reconstruction. The effect of notchplasty on tunnel placement and knee biomechanics with ACL reconstruction is not known.

Methods

Twelve (n = 12) porcine knees were tested using a robotic testing system. Four knee states were compared: (1) intact ACL, (2) ACL-deficient, (3) anatomic single bundle (SB) ACL reconstruction and (4) anatomic SB ACL reconstruction with a 5-mm notchplasty. The graft was fixed at 60° of flexion (full extension of porcine knee is 30°) with an 80-N tension. The knees were subjected to two loading conditions: an 89-N anterior tibial load (ATT) and 4 Nm internal (IR) and external tibial (ER) rotational torques. The kinematics and in situ force obtained from the different knee conditions were compared.

Results

There were no significant differences between pre- and post-notchplasty in the ER at 30° and 60° of knee flexion (n.s.). However, a significant difference was found between pre- and post-notchplasty in ATT at 30° and 60° of flexion (p < 0.05). The in situ force in the anatomic SB reconstruction with notchplasty was significant lower than the intact and anatomic reconstructed ACL pre-notchplasty at 30°, 60° and 90° of knee flexion (p < 0.05). In response to the IR tibial torque, there were significant differences between pre- and post-notchplasty in IR at 60° (p < 0.05) of knee flexion.

Conclusion

Notchplasty had greater effect on anterior stability than rotational stability. This change in knee kinematics could be detrimental to a healing bone graft, ligamentization and could lead to failure of the reconstruction in early post-operative period.     

Anterior cruciate ligament regeneration using mesenchymal stem cells and collagen type I scaffold in a rabbit model

Purpose

The objective of this study was to determine whether using mesenchymal stem cells (MSC) seeded in a collagen type I scaffold would be sufficient to regenerate the torn anterior cruciate ligament (ACL).

Methods

Anterior cruciate ligament transection was performed on both knees in 10 New Zealand rabbits and then repaired with as follows: suture alone (suture-treated group, n = 6), suture associated with collagen type I scaffold (collagen type I scaffold-treated group, n = 8) or suture associated with autologous MSC seeded on collagen type I scaffold (MSC/collagen type I scaffold-treated group, n = 6). At 12-week post-intervention, the animals were killed and the ACLs were characterised macroscopically and histologically. Data of the 3 groups were against normal ACL (normal group, n = 10).

Results

Macroscopic observation found that in MSC/collagen type I scaffold group, 33 % of specimens showed a complete ACL regeneration, with a tissue similar to the normal ACL. Regeneration was not observed in the group treated with suture alone or associated with collagen type I scaffold without cells. In the latter, only a reparative attempt at the ends was observed. Histological analysis of the regenerated ACL showed a tissue with organised collagen and peripheric vessels.

Conclusions

These results provide evidence that the use of MSC seeded in a collagen type I scaffold in the treatment of ACL injuries is associated with an enhancement of ligament regeneration. This MSC-based technique is a potentially attractive tool for improving the treatment of ACL ruptures.     

Double-bundle reconstruction results in superior clinical outcome than single-bundle reconstruction

Purpose

To compare the short- and long-term clinical outcomes of the double-bundle (DB) anterior cruciate ligament (ACL) reconstruction with those of single-bundle (SB) ACL reconstruction.

Methods

An electronic search of the database PubMed (1966–September 2011), EMBASE (1984–September 2011), and Cochrane Controlled Trials Register (CENTRAL; 3rd Quarter, 2011) was undertaken to identify relevant studies. Main clinical outcomes were knee stability measurements including KT-1000 arthrometer measurement, Pivot shift test, and Lachman test, and clinical outcome measurements including International Knee Documentation Committee (IKDC), Lysholm knee score, Tegner activity score, and complications.

Results

Eighteen studies were finally included in this meta-analysis, which were all classified as high risk of bias according to the Collaboration’s recommended tool. It is seen that compared to SB ACL reconstruction, DB ACL reconstruction results in a KT-1000 arthrometer outcome 0.63 and 1.00 mm closer to the normal knee in a short- and long-term follow-up, respectively. Our results also reveal that DB-treated patients have a significantly higher negative rate of the pivot shift test (p < 0.00001 and = 0.006 in a short- and long-term follow-up, respectively) and Lachman test (n.s. and p < 0.0001 in a short- and long-term follow-up, respectively) compared to SB-treated patients. As for the clinical outcome measurements, a significant difference is found between SB versus DB ACL reconstruction regarding the IKDC (p = 0.006 and < 0.0001 in a short- and long-term follow-up, respectively) and complications (p = 0.03), while there is no significant difference between the two groups regarding Lysholm knee score (n.s.) and Tegner activity score (n.s.).

Conclusion

Overall, double-bundle ACL reconstruction yields better clinical outcomes when compared to single-bundle ACL reconstruction.

Levels of evidence

II.     

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.

     

The iliotibial band in acute knee trauma: patterns of injury on MR imaging

Objective

To delineate the spectrum of knee injuries associated with sprains and tears of the distal iliotibial band (ITB).

Materials and methods

A retrospective review of 200 random MRI scans undertaken for acute knee trauma was performed. Scans were excluded if there was a history of injury over 4 weeks from the time of the scan, septic arthritis, inflammatory arthropathy, previous knee surgery, or significant artefact. In each scan, the ITB was scored as normal, minor sprain (grade 1), severe sprain (grade 2), and torn (grade 3). The menisci, ligaments, and tendons of each knee were also assessed.

Results

The mean age was 27.4 years (range, 9–69 years) and 71.5 % (n?=?143) of the patients were male. The ITB was injured in 115 cases (57.5 %). The next most common soft tissue structure injured was the anterior cruciate ligament (ACL) in 53.5 % of cases (n?=?107). Grade 1 ITB injury was seen in 90 of these 115 cases (45 %), grade 2 injury in 20 cases, and grade 3 injury in only five cases. There is a significant association between ITB injury and ACL rupture (p?p?Conclusions ITB injury is common in acute knee trauma and is associated with significant internal derangement of the knee, especially cruciate ligament rupture, posterolateral corner injury, and patellar dislocation.     

Biomechanical comparison of different graft positions for single-bundle anterior cruciate ligament reconstruction

Purpose

Recent reports have highlighted the importance of an anatomic tunnel placement for anterior cruciate ligament (ACL) reconstruction. The purpose of this study was to compare the effect of different tunnel positions for single-bundle ACL reconstruction on knee biomechanics.

Methods

Sixteen fresh-frozen cadaver knees were used. In one group (n = 8), the following techniques were used for knee surgery: (1) anteromedial (AM) bundle reconstruction (AM–AM), (2) posterolateral (PL) bundle reconstruction (PL–PL) and (3) conventional vertical single-bundle reconstruction (PL-high AM). In the other group (n = 8), anatomic mid-position single-bundle reconstruction (MID–MID) was performed. A robotic/universal force-moment sensor system was used to test the knees. An anterior load of 89 N was applied for anterior tibial translation (ATT) at 0°, 15°, 30° and 60° of knee flexion. Subsequently, a combined rotatory load (5 Nm internal rotation and 7 Nm valgus moment) was applied at 0°, 15°, 30° and 45° of knee flexion. The ATT and in situ forces during the application of the external loads were measured.

Results

Compared with the intact ACL, all reconstructed knees had a higher ATT under anterior load at all flexion angles and a lower in situ force during the anterior load at 60° of knee flexion. In the case of combined rotatory loading, the highest ATT was achieved with PL-high AM; the in situ force was most closely restored with MIDMID, and the in situ force was the highest AM–AM at each knee flexion angle.

Conclusion

Among the techniques, AM–AM afforded the highest in situ force and the least ATT.     

Anterior cruciate ligament reconstruction with 4-strand hamstring autograft and accelerated rehabilitation: a 10-year prospective study on clinical results, knee osteoarthritis and its predictors

Purpose

Analysis of long-term clinical and radiological outcomes after anterior cruciate ligament (ACL) reconstruction with special attention to knee osteoarthritis and its predictors.

Methods

A prospective, consecutive case series of 100 patients. Arthroscopic transtibial ACL reconstruction was performed using 4-strand hamstring tendon autografts with a standardized accelerated rehabilitation protocol. Analysis was performed preoperatively and 10 years postoperatively. Clinical examination included Lysholm and Tegner scores, IKDC, KT-1000 testing (MEDmetric Co., San Diego, CA, USA) and leg circumference measurements. Radiological evaluation included AP weight bearing, lateral knee, Rosenberg and sky view X-rays. Radiological classifications were according to Ahlbäck and Kellgren & Lawrence. Statistical analysis included univariate and multivariate logistic regressions.

Results

Clinical outcome A significant improvement (p < 0.001) between preoperative and postoperative measurements could be demonstrated for the Lysholm and Tegner scores, IKDC patient subjective assessment, KT-1000 measurements, pivot shift test, IKDC score and one-leg hop test. A pivot shift phenomenon (glide) was still present in 43 (50 %) patients and correlated with lower levels of activity (p < 0.022). Radiological outcome: At follow-up, 46 (53.5 %) patients had signs of osteoarthritis (OA). In this group, 33 patients (72 %) had chondral lesions (≥grade 2) at the time of ACL reconstruction. A history of medial meniscectomy before or at the time of ACL reconstruction increased the risk of knee OA 4 times (95 % CI 1.41–11.5). An ICRS grade 3 at the time of ACL reconstruction increased the risk of knee OA by 5.2 times (95 % CI 1.09–24.8). There was no correlation between OA and activity level (Tegner score ≥6) nor between OA and a positive pivot shift test.

Conclusion

Transtibial ACL reconstruction with 4-strand hamstring autograft and accelerated rehabilitation restored anteroposterior knee stability. Clinical parameters and patient satisfaction improved significantly. At 10-year follow-up, radiological signs of OA were present in 53.5 % of the subjects. Risk factors for OA were meniscectomy prior to or at the time of ACL reconstruction and chondral lesions at the time of ACL reconstruction.

Level of evidence

II.     

An isolated rupture of the posterior cruciate ligament results in reduced preoperative knee function in comparison with an anterior cruciate ligament injury

Purpose

To investigate differences in preoperative knee function (Knee Injury and Osteoarthritis Outcome Score, KOOS), the time period from injury to surgery, and associated injuries when comparing primary isolated posterior cruciate ligament (PCL) and primary anterior cruciate ligament (ACL) reconstructions.

Methods

Isolated primary ACL and PCL reconstructions registered in the Norwegian National Knee Ligament Registry from 2004 through 2010 were included (n = 71 primary PCLs and 9,649 primary ACLs). Linear regression analysis was used to evaluate the preoperative KOOS subscale values.

Results

The preoperative KOOS in the PCL group (n = 71) and ACL group (n = 9,649) was significantly different for the subscales symptoms (mean difference, ?8.4; 95 % CI: ?12.8 to ?4.0), pain (mean difference, ?15.9; 95 % CI: ?20.3 to ?11.4), activities of daily living (mean difference, ?12.9; 95 % CI: ?17.4 to ?8.4), sport and recreation (mean difference, ?15.9; 95 % CI: ?22.6 to ?9.3), and quality of life (mean difference, ?7.9; 95 % CI: ?12.4 to ?3.5). The primary isolated PCL-reconstructed knees had a median time from injury to surgery of 21 months in comparison with 8 months for ACL injuries. The ACL-injured knees had more associated injuries (meniscus and full-thickness cartilage lesions) than the PCL-injured knees.

Conclusion

Surgically treated knees with an isolated rupture of the PCL exhibited worse knee function preoperatively compared with knees with an isolated ACL injury; in addition, the delay to surgery was longer. Meniscal lesions were found more frequently in ACL-injured knees.

Level of evidence

Prospective cohort study, evidence Level I.     

Long-term follow-up of ACL reconstruction with hamstring autograft

Purpose

To investigate the differences in the incidence and severity of knee osteoarthritis (OA), joint space narrowing, knee laxity, and knee flexion and extension strength between an anterior cruciate ligament (ACL)-reconstructed knee and the contralateral non-reconstructed limb.

Methods

Retrospective case series of patients from a single surgeon that had an ACL reconstruction with a semitendinosus/gracilis autograft more than 12 years ago. Outcome measures included radiographic analysis, International Knee Documentation Committee Subjective Knee Evaluation Form (IKDC), KT-1000, Tegner Activity Level Scale, Lysholm Knee Score, ACL quality of life score (ACL-QOL) and knee flexor/extensor strength.

Results

Seventy-four patients consented and sixty-eight (43 male, 25 female) were included for analysis. Average age (SD) at the time of surgery was 31.2 (±9.1) years. At follow-up of 14.6 (1.9) years, 9 % had re-ruptured their ACL, whereas 5 % ruptured the contralateral ACL. Reconstructed knees had a greater incidence and severity of OA (P < 0.01). Medial meniscus surgery was a strong predictor of OA. Seventy-five per cent scored a normal or nearly normal knee on the IKDC. The mean Lysholm score was 75.8 % and Tegner Activity Level Scale scores decreased (P < 0.001) from the time of surgery. Knee extension strength was greater in the contralateral knee at speeds of 60°/s (P = 0.014) and 150°/s (P = 0.012).

Conclusions

Reconstructed knees have a greater incidence and severity of OA than non-reconstructed knees, which suggests degenerative changes are secondary to ACL rupture. Medial meniscus surgery is a strong predictor of OA. Despite this, 75 % of patients reported good outcomes.     

Association between varus alignment and post-traumatic osteoarthritis after anterior cruciate ligament injury

Purpose

To investigate the association between varus alignment and post-traumatic osteoarthritis (OA) after an anterior cruciate ligament (ACL) injury.

Methods

One hundred subjects with an acute complete ACL tear were followed for 15 years. Anterior–posterior radiographs of the tibiofemoral joint were obtained with a knee flexion of 20°, and the patellofemoral joint was examined with skyline view at 50° knee flexion. Joint space narrowing and osteophytes were graded in the tibiofemoral and patellofemoral joints in the injured (ACL) and uninjured knee according to the radiographic atlas of the Osteoarthritis Research Society International. The alignment of the uninjured, contralateral knee was measured at follow-up, using full-limb radiographs of leg with the knee in full extension. Alignment was expressed as the hip-knee-ankle (HKA) angle. Alignment was defined as valgus (HKA ≤178°), neutral (179°–181°) or varus (≥182°).

Results

Data from 68 subjects were included in the analysis. Varus alignment of the uninjured knee at follow-up appeared to be associated with OA of the injured knee 15 years after an ACL injury (odds ratio (95 % confidence interval) 3.9 (1.0–15.8, p = 0.052)).

Conclusions

Varus alignment of the uninjured knee at follow-up may be associated with OA of the injured knee 15 years after an ACL injury.

Level of evidence

II.     

Long-term follow-up of patellar tendon grafts or hamstring tendon grafts in endoscopic ACL reconstructions

Purpose

Several studies compare the short- and long-term results of anterior cruciate ligament (ACL) reconstruction using bone-patellar tendon-bone (BPTB) graft or double-looped semitendinosus and gracilis (DLSG) graft. However, no studies evaluate the long-term results of BPTB grafts fixed with metal interference screws and DLSG grafts fixed with the Bone Mulch Screw and the Washer Loc. This prospective randomized multicentre study has the null hypothesis that there is no difference in long-term outcome between the two procedures.

Methods

A total of 114 patients with a symptomatic ACL rupture were randomized to reconstruction with either a BPTB graft (N = 58) or a DLSG graft (N = 56). Follow-up was conducted after one, two and seven years. At the seven-year follow-up, 102 of the 114 patients (89%) were available for evaluation; however, 16 of these by telephone-interview only.

Results

Ten patients in the BPTB group and 19 patients in the DLSG group underwent additional knee surgery (P = 0.048), two and three, respectively, of these were ACL revisions (n.s.). The total flexion work was lower in the DLSG group (P = 0.001). The mean peak flexion torque and extension work, however, showed no difference between the groups. No significant differences were found between the groups regarding the Tegner activity score, the Lysholm functional score, the Knee injury and osteoarthritis outcome score (KOOS), subjective knee function, anterior knee pain or mobility. There was no significant difference in laxity between the groups on the Lachman test or the KT-1,000 maximum manual force test.

Conclusions

Both grafts and fixation methods resulted in satisfactory subjective outcome and objective stability. Both these methods can therefore be considered as suitable alternatives for ACL reconstructions.

Level of evidence

II.     

Combined PCL and PLC reconstruction in chronic posterolateral instability

Purpose

The posterolateral corner (PLC) is more likely to be injured in combination with the posterior cruciate ligament (PCL) or the anterior cruciate ligament than in isolation. This leads to instability of the knee and loss of function. We hypothesised that combined PCL and PLC reconstruction would restore sufficient stability to allow improvement in patient symptoms and function.

Methods

19 patients who underwent arthroscopic-assisted single-bundle PCL and PLC reconstruction by a single surgeon were analysed retrospectively. The PLC reconstruction was a modified Larson reconstruction of the lateral collateral ligament and the popliteofibular ligament. The IKDC and Tegner scores were used to assess outcome. Dial test and varus laxity were used to assess improvements in clinical laxity. Posterior laxity was tested using the KT-1000.

Results

The mean follow-up was 38 months (±(2× standard deviations), ±12.3). There were no postoperative complications. All patients had less than 5 mm posterior step-off. 17 of 19 patients had negative dial and varus stress tests. Measured range of motion was reduced by a mean of 10°, but patients did not report any daily activities restrictions. Tegner scores improved from a median pre-operative value of 2 (range 1–4) to 6 (4–9) at final follow-up. The mean postoperative IKDC score was 86 (±11).

Conclusions

Subjectively, the knee stability achieved allowed daily activities. However, there were remaining abnormalities in range of motion, posterior drawer and rotational laxity, suggesting that normal knee laxity was not restored.

Level of evidence

IV.     

3-T MRI assessment of osteophyte formation in patients with unilateral anterior cruciate ligament injury and reconstruction

Objective

To define the number and distribution of osteophytes (OPs) in bilateral knee MRI (magnetic resonance imaging) of patients with unilateral anterior cruciate ligament (ACL) rupture.

Materials and methods

Bilateral knee MRIs of 20 patients with unilateral ACL rupture and reconstruction were retrospectively analyzed for OPs. OPs were graded following the KOSS (knee OA scoring system) classification and their compartmental distribution was assessed following the WORMS (Whole-Organ Magnetic Resonance Imaging Score) classification.

Results

All examined knees revealed OPs. Knees with ACL rupture showed significant (p?<?0.001) higher total numbers of OPs (mean 11.6; SD?±?4.4) than knees with intact ACL (mean 5.1; SD?±?2.3). Knees with ACL rupture showed increased OP formation in all knee compartments with predominance of marginal OPs in the lateral femorotibial compartment especially on the tibia.

Conclusions

Our results show that after knee injury with ACL rupture and reconstruction, all knee compartments were involved in post-traumatic increase of OP formation. The most affected compartment was the lateral femorotibial compartment on the tibial side.     

Combined reconstruction of the posterior cruciate ligament and medial collateral ligament using a single femoral tunnel

Purpose

Lesions of the medial collateral ligament (MCL) are the most common knee ligament injuries, and lesions associated with the anterior cruciate ligament or the posterior cruciate ligament (PCL) in knee dislocations should be reconstructed to prevent failure of the central pivot reconstruction. The purpose of this study was to evaluate the outcomes of combined PCL/MCL reconstruction using a single femoral tunnel with a minimum 2-year follow-up.

Method

A retrospective study of thirteen patients with combined PCL/MCL injuries was conducted. The patients underwent PCL and MCL reconstruction using an Achilles tendon allograft with a single tunnel in the medial femoral condyle, thereby avoiding tunnel conversion.

Results

All patients achieved a range of motion of at least 100°. The mean loss of extension and flexion values compared to the contralateral side was 1° ± 2° and 9° ± 10°, respectively. Our results included 26 reconstructions with three (11.5 %) failures, two in the PCL (15.3 %) and one in the MCL (7.6 %), in three different patients. In the final evaluation, the mean IKDC subjective score was 71.63 ± 16.23, the mean Lysholm score was 80.08 ± 13.87, and the median Tegner score was 6 (range = 2–7).

Conclusion

The PCL/MCL reconstruction technique using a single femoral tunnel and an Achilles tendon allograft is safe, avoids the convergence of tunnels in the medial femoral condyle, has excellent results, and is reproducible.

Level of evidence

IV.

     

Time from ACL injury to reconstruction and the prevalence of additional intra-articular pathology: is patient age an important factor?

Purpose

Meniscus and cartilage lesions have been reported to be prevalent during delayed reconstruction of anterior cruciate ligament (ACL) injuries. Relatively, little work has been done exploring the influence of patient age on this relationship. The purpose of this study is to determine whether the effect of time from ACL injury to reconstruction on the prevalence of associated meniscal and chondral injury is influenced by patient age. It was hypothesized that patients in whom the time from ACL injury to reconstruction exceeds 12 weeks will exhibit an increased prevalence of medial compartment pathology relative to those reconstructed within 12 weeks of injury in patients of all ages.

Methods

Data detailing time from ACL injury to reconstruction and the prevalence of intra-articular findings were obtained in 311 of 489 consecutive patients undergoing primary isolated ACL reconstruction. Patients were divided into two groups based on whether the time from ACL injury to reconstruction was <12 weeks or at least 12 weeks. The prevalence of associated intra-articular injury was then compared between the two groups. Patients were then stratified based on age (22 years and under vs. over the age of 22), and the analysis was repeated on both groups.

Results

Analysis of all patients together revealed a significantly higher prevalence of medial meniscus injury (p = 0.013) and medial compartment chondral injury (p < 0.0005) in patients in whom the time from ACL injury to reconstruction exceeded 12 weeks. The prevalence of lateral meniscal injury did not increase with increasing time ACL injury to surgery. Among patients aged 22 years and under, there was no increase in the prevalence of intra-articular pathology in any compartment in the late reconstruction group. In contrast, among patients over the age of 22, there was a significant increase in the prevalence of medial chondral injury (p = 0.042) in the late reconstruction group.

Conclusion

The prevalence of injuries to the meniscus and articular cartilage in the medial compartment of the knee is increased with increasing time from ACL injury to reconstruction. This relationship may vary depending on patient age. Patients over the age of 22 exhibit a higher prevalence of intra-articular injury with delayed reconstruction, while no such differences are noted among younger patients.

Level of evidence

Retrospective comparative study, Level III.     

Is osteoarthritis an inevitable consequence of anterior cruciate ligament reconstruction? A meta-analysis

Purpose

Although the occurrence of early osteoarthritis (OA) is commonly associated with a history of anterior cruciate ligament (ACL) reconstruction, its exact prevalence in these patients remains unknown. The goal of this study was to review the current literature on long-term radiographic outcome after autologous ACL reconstruction and subsequently perform a meta-analysis to obtain evidence-based prevalences of OA at a mean of 10 years after surgery. In addition, this report aimed at identifying the relationship between meniscal status and the occurrence of radiographic OA in the ACL reconstructed knee.

Methods

A systematic review of the literature was performed in PubMed MEDLINE, EMBASE and Cochrane Library databases to identify all studies concerning radiographic outcome after autologous ACL reconstruction with a follow-up of minimum 10 years. Meta-analyses were performed to obtain the average prevalence of OA and the difference between patients with and without meniscectomy. Considered study estimates were the log-transformed odds and odds ratios, the latter expressing the effect of meniscectomy on OA.

Results

A total of 16 studies could be included for meta-analysis, accounting for 1554 ACL reconstructions performed between 1978 and 1997. Of these knees, 453 (28 %) showed radiological signs of osteoarthritis (IKDC grade C or D). Furthermore, 50 % of the patients with meniscectomy had osteoarthritis, compared with 16 % of the patients without meniscectomy. The combined odds ratio for meniscectomy equals 3.54 (95 % CI 2.56–4.91).

Conclusions

The main finding of this meta-analysis is that the prevalence of radiographic knee OA after ACL reconstruction is lower than commonly perceived. However, associated meniscal resection dramatically increases the risk for developing OA.

Level of evidence

Level III.     

Functional recovery after anterior cruciate ligament reconstruction, a study of health-related quality of life based on the Swedish National Knee Ligament Register

Purpose

To restore functional stability of the knee joint and to prevent secondary injuries to the cartilage and menisci are the main goals of an anterior cruciate ligament (ACL) reconstruction. Functional stability can be assessed by health-related quality of life questionnaires, but characterising differences between a satisfactory and non-satisfactory result can be challenging.

Methods

The aim of this study based on the Swedish National Knee Ligament Register was to find predictors for a satisfactory result defined as functional recovery (FR) or a non-satisfactory result defined as treatment failure (TF), with special emphasis on waiting time before surgery and additional injuries. FR was defined as a Knee Osteoarthritis Outcome Score (KOOS) above: 90 for Pain, 84 for Symptoms, 91 for ADL, 80 for Sport/Rec and 81 for quality of life (QoL). TF was defined as a KOOS, QoL < 44.

Results

A complete KOOS was available for 41.4 % of a cohort of 8,584 patients 2 years after the ACL reconstruction. Of all patients, 19.7 % were FR and 28.9 % were TF. Male gender was a predictor for FR. Previous surgery of the menisci and a patella graft was predictors for TF and negative predictors for FR. A medial meniscus suture or resection at the time of reconstruction was a predictor for TF. Waiting time was a predictor for medial meniscus and cartilage injury at the time of reconstruction.

Conclusions

Functional recovery after an ACL reconstruction can be achieved; gender and additional injuries are important predictors for a functional recovery. To time surgery early, that is, before recurring giving ways has occurred is essential to decrease additional injuries and increase the chance of functional recovery.

Level of evidence

II.