Tibial tunnel widening following anterior cruciate ligament reconstruction: A retrospective seven-year study evaluating the effects of initial graft tensioning and graft selection

Lateral extra-articular tenodesis does not enhance ACL graft healing, however, does reduce graft tunnel widening

PURPOSE

The study hypothesized that the addition of lateral extra-articular tenodesis (LEAT) in anterior cruciate ligament reconstruction (ACLR) had a significant effect on ACL graft healing.

METHODS

A total of 80 patients were divided into two cohorts matched for gender, age, body mass index, time from surgery to post-operative MRI and graft diameter. Forty patients underwent ACL reconstruction alone, while 40 underwent ACLR in addition to LEAT. Patients underwent a magnetic resonance imaging scan at 12 months post-surgery; tunnel apertures were measured using multiplanar reformation, graft healing was assessed using signal-to-noise quotient (SNQ) in three regions of interest and finally graft maturity and integration were classified using the Howell and Ge scale, respectively. In addition, clinical evaluation and patient-reported outcome measures were collected.

RESULTS

The mean femoral tunnel widening at 12 months post-surgery was 39.8 ± 14.0% in the ACLR + LEAT group and 55.2 ± 12.7% in the ACLR alone group (p < 0.05). The mean tibial tunnel widening was 29.3 ± 12.7% in the ACLR + LEAT group and 44.4 ± 12.1% in the ACLR group (p < 0.05). The mean adjusted graft SNQ was 9.0 ± 14.9 in the ACLR + LEAT group and 9.5 ± 11.4 in the ACLR group (n.s.).

CONCLUSION

At 1 year post-operatively, we noted significantly less femoral and tibial tunnel widening in the ACLR + LEAT group. LEAT did not result in a statistically significant effect on graft healing.

LEVEL OF EVIDENCE

Level III.

Hyperbaric oxygen therapy enhances graft healing and mechanical properties after anterior cruciate ligament reconstruction: An experimental study in rabbits

Hyperbaric oxygen therapy (HBOT) has proven successful in wound healing. However, its potential effects on anterior cruciate ligament (ACL) injuries remain uncertain. This study aimed to investigate the impact of HBOT on graft healing following ACL reconstruction in rabbits. Male New Zealand rabbits underwent ACL reconstruction and were randomly divided into two groups: the HBOT group and the ambient air group. The HBOT group received 100% oxygen at 2.5 atmospheres absolute for 2 h daily for 5 consecutive days, starting from the first day after surgery. The ambient air group was maintained in normal room air throughout the entire period. After 12 weeks following the surgery, animals were euthanized, and their knees were harvested for analysis. The HBOT group demonstrated superior graft maturation and integration in comparison to the ambient air group, as evidenced by lower graft signal intensity on magnetic resonance imaging, decreased femoral and tibial tunnel size, and higher bone mineral density values on high-resolution peripheral quantitative computed tomography scans. Additionally, biomechanical testing indicated that the HBOT group had greater load to failure and stiffness values than the ambient air group. In conclusion, the adjuvant use of HBOT improved ACL graft maturation and integration, reduced tunnel widening, and enhanced the biomechanical properties of the graft. These results may provide important insights into the potential clinical application of HBOT as a therapeutic intervention to enhance graft healing after ACL reconstruction, paving the way for further research in this area.

[Research progress of tibial-graft fixation methods on anterior cruciate ligament reconstruction]

Objective

To review the studies about the tibial-graft fixation methods on anterior cruciate ligament (ACL) reconstruction, in order to provide clinical reference.

Methods

The literature about the tibial-graft fixation methods on ACL reconstruction at home and abroad was extensively reviewed, and the factors that affect the selection of fixation methods were summarized.

Results

The knee flexion angle, graft tension, and graft fixation device are mainly considered when the tibial-graft was fixed on ACL reconstruction. At present, the graft is mainly fixed at 0°/30° of knee flexion. The study shows that the knee joint is more stable after fixed at 30°, while the incidence of knee extension limitation decrease after fixed at 0°. In terms of graft tension, a good effectiveness can be obtained when the tension level is close to 90 N or the knee flexion is 30° to recover the affected knee over-restrained 2 mm relative to the healthy knee. In terms of the graft device, the interference screw is still the most commonly used method of tibial-graft fixation, with the development of all-inside ACL reconstruction in recent years, the cortical button fixation may become the mainstream.

Conclusion

Arthroscopic reconstruction is the main treatment of ACL rupture at present. However, there is no optimal fixation method for the tibial-graft, the advantages and disadvantages of each fixation methods need to be further studied.

Bone-patellar tendon-bone versus two- and four-strand hamstring tendon autografts for ACL reconstruction in young adults: a Bayesian network meta-analysis

Bone-patellar tendon-bone (BPTB), two- and four-strand hamstring tendon (4SHT and 2SHT, respectively) are the most common autografts used for anterior cruciate ligament (ACL) reconstruction. The present study compared BPTB, 2SHT, and 4SHT for ACL reconstruction in terms of joint laxity, patient reported outcome measures (PROMs), rate of failure and anterior knee pain (AKP). The time to return to sport and the peak torque between the autografts were also compared. Finally, prognostic factors leading to worse outcomes were also investigated. It was hypothesized that all grafts yield similar proprieties in terms of joint laxity, patient reported outcome measures (PROMs) and rate of failure, but that the BPTB autograft causes a greater rate of anterior knee pain (AKP). The literature search was conducted. All clinical trials comparing BTPB and/or 2SHT, and/or 4SHT were accessed. Grafts other than BTPB and/or 4SHT and/or 2SHT were not considered. Articles reporting outcomes of allografts or synthetic grafts were not eligible, nor were those concerning revision settings. Articles reporting ACL reconstruction in patients with multi-ligament damage were also not eligible. Data from 95,575 procedures were retrieved. The median length of follow-up was 36 months. The median age of the patients was 27.5 years. With regard to joint laxity, similarity was found in terms of Lachman and Pivot shift tests between all three autografts. The BPTB demonstrated the greatest stability in terms of instrumental laxity. BPTB demonstrated the greatest PROMs. BPTB demonstrated the greatest rate of AKP, while AKP in 2SHT and 4SHT was similar. Concerning failure, statistically significant inconsistency was found (P = 0.008). The 4SHT demonstrated the quickest return to sport, followed by BPTB, and 2SHT. There was evidence of a negative association between the time span between injury to surgery, Lysholm score (P = 0.04), and Tegner scale (P = 0.04). Furthermore, there was evidence of a weak positive association between the time span between injury to surgery and return to sport (P = 0.01). BPTB may result in lower joint laxity, greater PROMs, and greater peak flexion torque compared to 2SHT and 4SHT autografts. On the other hand, BPTB reported the lowest peak extension torque and the greatest rate of AKP. Finally, a longer time span between injury and surgery negatively influences outcome.

Acceptable clinical outcomes despite high reoperation rate at minimum 12-month follow-up after concomitant arthroscopically assisted anterior cruciate ligament reconstruction and medial meniscal allograft transplantation

BACKGROUND

Single-stage medial meniscus allograft transplantation (MAT) with concomitant anterior cruciate ligament reconstruction (ACLR) is a technically challenging procedure for management of knee pain and instability in younger patients, but clinical and functional outcomes data are sparse. The purpose of this study was to assess surgical and patient-reported outcomes following concomitant ACLR and medial MAT.

METHODS

We conducted a retrospective case series of patients who underwent medial MAT with concomitant primary or revision ACLR at our institution from 2010 to 2021 and had minimum 12-month follow-up. Complications, reoperations, visual analog scale (VAS) pain, satisfaction, Lysholm score, return to sport, and return to work outcomes were assessed. Patient-Reported Outcomes Measurement Information System (PROMIS) Pain Interference, Pain Intensity, and Physical Function Scores were used to measure patients' functional status relative to the US population. P-values < 0.05 were considered significant.

RESULTS

The cohort consisted of 17 knees of 16 individual patients. The cohort was majority male (82.4%) with mean age of 31.9 years (range 19-49 years) and mean body mass index (BMI) of 27.9 kg/m² (range 22.5-53.3 kg/m²). Mean follow-up time was 56.8 months (range 13-106 months). Most patients underwent revision ACLR (64.7%). The 1-year reoperation rate was high (23.5%), with two patients (11.8%) tearing their meniscus graft. Patient-reported outcomes indicated low VAS pain (mean 2.2), high satisfaction (mean 77.9%), and fair Lysholm score (mean 81.1). Return to work rate was high (92.9%), while return to sport rate was low (42.9%). Postoperative PROMIS scores were comparable or superior to the national average and correlated significantly with patient satisfaction (p < 0.05).

CONCLUSIONS

The concomitant ACLR and MAT procedure is associated with excellent knee pain and functional outcomes and high rate of return to work after surgery, though the 1-year reoperation rate is high and rate of return to sport is low.

LEVEL OF EVIDENCE

IV.

Descriptive Characteristics and Outcomes of Patients Undergoing Revision Anterior Cruciate Ligament Reconstruction With and Without Tunnel Bone Grafting

BACKGROUND

Lytic or malpositioned tunnels may require bone grafting during revision anterior cruciate ligament reconstruction (rACLR) surgery. Patient characteristics and effects of grafting on outcomes after rACLR are not well described.

PURPOSE

To describe preoperative characteristics, intraoperative findings, and 2-year outcomes for patients with rACLR undergoing bone grafting procedures compared with patients with rACLR without grafting.

STUDY DESIGN

Cohort study; Level of evidence, 3.

METHODS

A total of 1234 patients who underwent rACLR were prospectively enrolled between 2006 and 2011. Baseline revision and 2-year characteristics, surgical technique, pathology, treatment, and patient-reported outcome instruments (International Knee Documentation Committee [IKDC], Knee injury and Osteoarthritis Outcome Score [KOOS], Western Ontario and McMaster Universities Osteoarthritis Index, and Marx Activity Rating Scale [Marx]) were collected, as well as subsequent surgery information, if applicable. The chi-square and analysis of variance tests were used to compare group characteristics.

RESULTS

A total of 159 patients (13%) underwent tunnel grafting-64 (5%) patients underwent 1-stage and 95 (8%) underwent 2-stage grafting. Grafting was isolated to the femur in 31 (2.5%) patients, the tibia in 40 (3%) patients, and combined in 88 patients (7%). Baseline KOOS Quality of Life (QoL) and Marx activity scores were significantly lower in the 2-stage group compared with the no bone grafting group (P≤ .001). Patients who required 2-stage grafting had more previous ACLRs (P < .001) and were less likely to have received a bone-patellar tendon-bone or a soft tissue autograft at primary ACLR procedure (P≤ .021) compared with the no bone grafting group. For current rACLR, patients undergoing either 1-stage or 2-stage bone grafting were more likely to receive a bone-patellar tendon-bone allograft (P≤ .008) and less likely to receive a soft tissue autograft (P≤ .003) compared with the no bone grafting group. At 2-year follow-up of 1052 (85%) patients, we found inferior outcomes in the 2-stage bone grafting group (IKDC score = 68; KOOS QoL score = 44; KOOS Sport/Recreation score = 65; and Marx activity score = 3) compared with the no bone grafting group (IKDC score = 77; KOOS QoL score = 63; KOOS Sport/Recreation score = 75; and Marx activity score = 7) (P≤ .01). The 1-stage bone graft group did not significantly differ compared with the no bone grafting group.

CONCLUSION

Tunnel bone grafting was performed in 13% of our rACLR cohort, with 8% undergoing 2-stage surgery. Patients treated with 2-stage grafting had inferior baseline and 2-year patient-reported outcomes and activity levels compared with patients not undergoing bone grafting. Patients treated with 1-stage grafting had similar baseline and 2-year patient-reported outcomes and activity levels compared with patients not undergoing bone grafting.

Tibial graft fixation methods and bone tunnel enlargement: A comparison between the TensionLoc implant system and the double-spike plate

Background/objective

TensionLoc (Arthrex, Naples, Florida, USA), a tibial graft fixation system for anterior cruciate ligament (ACL) reconstruction, is expected to apply the preoperatively determined level of graft tension and allow setting of lower initial tension. Considering its mechanism, we hypothesised that TensionLoc would prevent postoperative bone tunnel enlargement (TE) through fixation with lower initial tension. Therefore, the present study aimed to compare TE between ACL reconstructions using the double-spike plate (DSP; Smith and Nephew, Andover, Massachusetts) and TensionLoc implant system.

Methods

A total of 40 patients who underwent anatomical single-bundle ACL reconstruction with a hamstring tendon graft were retrospectively analysed. In the group in which DSP and screw were used, the initial graft tension was set to 40 N at 20° of knee flexion (group D). In the other group in which TensionLoc was used, the initial graft tension was set to 30 N at 20° of knee flexion (group T). Both groups included 20 patients each. Tunnel areas were measured using computed tomography images at one week and three months after surgery, and the TE ratio was calculated according to the following equation: TE ratio (%) = (tunnel area at three months after surgery - tunnel area at one week after surgery)/tunnel area at one week after surgery × 100.

Results

The femoral TE ratios were significantly higher in group T (80.5% ± 28.8%) than in group D (45.5% ± 34.6%) (p = 0.001). However, the tibial TE ratios did not significantly differ between the two groups.

Conclusion

Compared with ACL reconstruction using DSP and screw, ACL reconstruction using TensionLoc fixed the graft with lower initial tension but showed greater femoral TE and restricted knee extension in the early postoperative period.

Comparison of Bioabsorbable and Metallic Interference Screws for Graft Fixation During ACL Reconstruction: A Meta-analysis of Randomized Controlled Trials

Background

Bioabsorbable interference screws and metallic interference screws are both widely used for graft fixation, but it remains unclear which screw type is superior.

Purpose

To compare clinical outcomes and complications between bioabsorbable and metallic interference screws for anterior cruciate ligament reconstruction (ACLR).

Study Design

Systematic review; Level of evidence, 1.

Methods

The literature was searched for relevant randomized controlled trials published between 1966 and 2020. Two investigators independently assessed risk of bias in the included studies, and data were pooled to calculate mean differences (MDs) for continuous outcomes and risk ratios (RRs) for dichotomous outcomes, together with 95% CIs. Meta-analysis was performed using a random- or fixed-effects model, depending on the heterogeneity in the data.

Results

Included were 14 randomized controlled trials involving 1032 patients who underwent ACLR: 528 patients with bioabsorbable screws and 504 patients with metallic screws. The 2 groups did not differ significantly in International Knee Documentation Committee score (RR, 1.04; 95% CI, 0.97 to 1.11), Lysholm score (MD, 0.59; 95% CI, -0.46 to 1.63), range of motion deficit (RR, 0.95; 95% CI, 0.67 to 1.34), positive pivot-shift test (RR, 0.87; 95% CI, 0.61 to 1.24), positive Lachman test (RR, 0.82; 95% CI, 0.48 to 1.39), or KT-1000 arthrometer value (MD, 0.01; 95% CI, -0.16 to 0.18). However, bioabsorbable screws were associated with a significantly higher risk of complications (RR, 1.70; 95% CI, 1.16 to 2.50), such as graft rupture, joint effusion, and infection.

Conclusion

The results of this review showed that there was no difference between metallic and bioabsorbable screws for ACLR in terms of subjective knee function or knee laxity, but metallic interference screws had fewer complications.

Femoral Tunnel Widening After Double-Bundle Anterior Cruciate Ligament Reconstruction With Hamstring Autograft Produces a Small Shift of the Tunnel Position in the Anterior and Distal Direction: Computed Tomography-Based Retrospective Cohort Analysis

PURPOSE

To determine whether the femoral tunnel position remains in an anatomical footprint after tunnel widening and shifting.

METHODS

Patients who underwent unilateral double-bundle anterior cruciate ligament reconstruction with hamstring autograft and performed computed tomography scan evaluation at the time of 5 days and 1 year postoperatively were included in this retrospective cohort study. Three-dimensional models of the femur and femoral tunnels were reconstructed from computed tomography scan data. The location of the tunnel center and tunnel margins in the anatomical coordinate system, and the mean shifting distance of tunnel center and margin were measured with image analysis software during the period. The change of tunnel center location in Bernard quadrant was confirmed if the tunnel center remained within the boundaries of anatomical position after tunnel widening.

RESULTS

A total of 56 patients satisfied the inclusion criteria. The mean shifting distance of AM and PL tunnel centers were 1.7 ± 0.9 mm and 1.6 ± 0.6 mm. The Tunnel margin of the anteromedial (AM) and posteromedial (PL) tunnels were shifted to 2.5 ± 1.3 mm and 2.6 ± 1.4 mm in the anterior direction, and 1.4 ± 0.9 mm and 1.0 ± 0.7 mm in the distal direction, respectively. Among the anatomical located tunnel, 97% (32/33) and 87.1% (27/31) of AM and PL tunnel centers remained in a range of anatomical footprint. The tunnel center was shifted from the anatomical position into a nonanatomical position in 3% (1/33) of the AM tunnel and 12.9% (4/31) of PL tunnel after tunnel widening. The tunnel location which shifted nonanatomically were relatively anterior and distal position.

CONCLUSIONS

Tunnel widening shifts the tunnel position to the anterior and distal direction, which could change the initial tunnel position. Nevertheless, the majority of tunnel positions remained in the anatomical position after tunnel widening and shifting.

LEVEL OF EVIDENCE

Level III, retrospective cohort study.

Long-term outcomes of anterior cruciate ligament reconstruction surgery: 2020 OREF clinical research award paper

ACL injuries place the knee at risk for post-traumatic osteoarthritis (PTOA) despite surgical anterior cruciate ligament (ACL) reconstruction. One parameter thought to affect PTOA risk is the initial graft tension. This randomized controlled trial (RCT) was designed to compare outcomes between two graft tensioning protocols that bracket the range commonly used. At 7 years postsurgery, we determined that most outcomes between the two tension groups were not significantly different, that they were inferior to an uninjured matched control group, and that PTOA was progressing in both groups relative to controls. The trial database was also leveraged to gain insight into mechanisms of PTOA following ACL injury. We determined that the inflammatory response at the time of injury undermines one of the joint's lubricating mechanisms. We learned that patients continue to protect their surgical knee 5 years postinjury compared to controls during a jump-pivot activity. We also established that presurgical knee function and mental health were correlated with symptomatic PTOA at 7 years, that there were specific anatomical factors associated with poor outcomes, and that there were no changes in outcomes due to tunnel widening in patients receiving hamstring tendon autografts. We also validated a magnetic resonance imaging technique to noninvasively assess graft strength. In conclusion, the RCT determined that initial graft tensioning does not have a major influence on 7-year outcomes. Therefore, surgeons can reconstruct the ACL using a graft tensioning protocol that is within the window of the two graft tensioning techniques evaluated in this RCT.

[Arthroscopic reinforced reconstruction of anterior cruciate ligament with autologous hamstring tendon and anchor suture band]

Objective

To investigate the effectiveness of arthroscopic reinforced reconstruction of anterior cruciate ligament (ACL) with autologous hamstring tendon combined with anchor suture band.

Methods

Between February 2016 and March 2018, 60 patients who were to be treated with arthroscopic ACL reconstruction and met the selection criteria were selected in the study. Among them, 30 cases were reconstructed with autologous hamstring tendon combined with anchor suture band (trial group), and 30 cases were reconstructed with simple autologous hamstring tendon (control group). There was no significant difference in gender, age, disease duration, cause of injury, injury side, and preoperative Lysholm score, Tegner score, and International Knee Documentation Committee (IKDC) score between the two groups ( P>0.05). After reconstruction, the patients in the trial group were allowed to start knee flexion and extension activities early without wearing an adjustable brace, while the patients in the control group were required to wear an adjustable brace for 12 weeks. The knee joint function (Lysholm score, Tegner score, IKDC score) and stability (Lachman test and pivot shift test) were compared between the two groups after operation.

Results

There was no significant difference in graft diameter between the two groups ( t=1.061, P=0.115). Compared with the control group, the operation time of the trial group was significantly different ( t=4.924, P=0.000). All incisions healed primarily. In the control group, the intramuscular venous thrombosis occurred in 2 cases after operation. Both groups were followed up 18 months. The Lysholm score, Tegner score, and IKDC score of the two groups at each time point after operation were significantly higher than those before operation ( P<0.05); the above scores in the trial group were significantly higher than those in the control group at 3, 6, and 9 months after operation ( P<0.05); there was no significant difference between the two groups at 18 months after operation ( P>0.05). There was no significant difference in Lachman test results between the two groups at each time point after operation ( P>0.05). There was a significant difference in pivot shift test results at 6 months after operation between the two groups ( P<0.05); but there was no significant difference at other time points ( P>0.05).

Conclusion

The effectiveness of ACL reinforcedreconstruction with autologous hamstring tendon combined with anchor suture band is satisfactory. Compared with using autologous hamstring tendon alone, it has better initial strength and joint stability, and is more conducive to early postoperative functional exercise and functional recovery of knee joint.

An Autograft for Anterior Cruciate Ligament Reconstruction Results in Better Biomechanical Performance and Tendon-Bone Incorporation Than Does a Hybrid Graft in a Rat Model

BACKGROUND

The biomechanical and tendon-bone incorporation properties of allograft-augmented hybrid grafts for anterior cruciate ligament (ACL) reconstruction compared with traditional autografts are unknown.

HYPOTHESIS

Using an autograft for ACL reconstruction yields better results on biomechanical testing, radiographic analysis, and histological evaluation versus using a hybrid graft.

STUDY DESIGN

Controlled laboratory study.

METHODS

A total of 66 adult male Sprague Dawley rats underwent unilateral ACL reconstruction with an autograft (AT group; n = 33) or a hybrid graft (HB group; n = 33). The grafts used in both groups were harvested from the peroneus longus tendon and were fixed by suturing to the surrounding periosteum. Samples were harvested for biomechanical testing, micro-computed tomography (CT), and histological evaluation at 4, 8, and 12 weeks postoperatively. Bone tunnels on the femoral and tibial sides were divided into 3 subregions: intra-articular (IA), midtunnel (MT), and extra-articular (EA). A cylinder-like volume of interest in the bone tunnel and a tubular-like volume of interest around the bone tunnel were used to evaluate new bone formation and bone remodeling, respectively, via micro-CT.

RESULTS

In the AT group, there were significantly higher failure loads and stiffness at 8 weeks (failure load: 3.04 ± 0.40 vs 2.09 ± 0.54 N, respectively; P = .006) (stiffness: 3.43 ± 0.56 vs 1.75 ± 0.52 N/mm, respectively; P < .001) and 12 weeks (failure load: 9.10 ± 1.13 vs 7.14 ± 0.94 N, respectively; P = .008) (stiffness: 4.45 ± 0.75 vs 3.36 ± 0.29 N/mm, respectively; P = .008) than in the HB group. With regard to new bone formation in the bone tunnel, in the AT group, the bone volume/total volume (BV/TV) was significantly higher than in the HB group on the tibial side at 8 weeks (IA: 22.21 ± 4.98 vs 5.16 ± 3.98, respectively; P < .001) (EA: 19.66 ± 7.19 vs 10.85 ± 2.16, respectively; P = .030) and 12 weeks (IA: 30.50 ± 5.04 vs 17.11 ± 7.31, respectively; P = .010) (MT: 21.15 ± 2.58 vs 15.55 ± 4.48, respectively; P = .041) (EA: 20.75 ± 3.87 vs 10.64 ± 3.94, respectively; P = .003). With regard to bone remodeling around the tunnel, the BV/TV was also significantly higher on the tibial side at 8 weeks (MT: 33.17 ± 8.05 vs 15.21 ± 7.60, respectively; P = .007) (EA: 25.19 ± 6.38 vs 13.94 ± 7.10, respectively; P = .030) and 12 weeks (IA: 69.46 ± 4.45 vs 47.80 ± 6.16, respectively; P < .001) (MT: 33.15 ± 3.88 vs 13.76 ± 4.07, respectively; P < .001) in the AT group than in the HB group. Sharpey-like fibers had formed at 8 weeks in the AT group. A large number of fibroblasts withdrew at 12 weeks. In the AT group, the width of the interface was significantly narrower at 4 weeks (85.86 ± 17.49 vs 182.97 ± 14.35 μm, respectively; P < .001), 8 weeks (58.86 ± 10.99 vs 90.15 ± 11.53 μm, respectively; P = .002), and 12 weeks (42.70 ± 7.96 vs 67.29 ± 6.55 μm, respectively; P = .001) than in the HB group.

CONCLUSION

Using an autograft for ACL reconstruction may result in improved biomechanical properties and tendon-bone incorporation compared with a hybrid graft.

CLINICAL RELEVANCE

Augmenting small autografts with allograft tissue may result in decreased biomechanical performance and worse tendon-bone incorporation, increasing the risk of graft failure.

Magnetic resonance imaging of the knee

Knee pain is frequently seen in patients of all ages, with a wide range of possible aetiologies. Magnetic resonance imaging (MRI) of the knee is a common diagnostic examination performed for detecting and characterising acute and chronic internal derangement injuries of the knee and helps guide patient management. This article reviews the current clinical practice of MRI evaluation and interpretation of meniscal, ligamentous, cartilaginous, and synovial disorders within the knee that are commonly encountered.

Editorial Commentary: Anatomic or Not, the Tunnel Will Get Wider!

In our experience, arthroscopic tunnel widening is one of the major complications after anterior cruciate ligament (ACL) reconstruction. Even though this complication doesn't require an acute correction or intervention, patients with failed ACL reconstruction along with tunnel widening may need a 2-stage revision in which we have to fill the gap in the tunnels first. Otherwise, this tunnel widening after ACL reconstruction doesn't affect the clinical outcomes of the primary surgery and it won't affect the success of the surgery in the aspects of clinical and functional outcomes.

Long-term arthroscopic assessment of intra-articular allografts for treatment of spontaneous cranial cruciate ligament rupture in the dog

OBJECTIVE

To assess the 12-month survival of intra-articular, decellularized allografts for the treatment of cranial cruciate ligament disease (CCLD) in dogs.

STUDY DESIGN

Prospective case series.

ANIMALS

Twenty client-owned dogs with spontaneous CCL rupture.

METHODS

Affected stifles were treated solely by implantation of an intra-articular, decellularized, deep digital flexor tendon allograft. Functional outcome was evaluated at baseline and at 6 and 12 months after surgery with the Liverpool Osteoarthritis for Dogs questionnaire and force platform gait analysis. At 12 months after surgery, dogs underwent arthroscopy to visually assess the allografts.

RESULTS

Scores on owner questionnaires (improved 62.5%; P = .005) and ground reaction forces (improved 34.4%; P = .017) were improved in all dogs 12 months after surgery. Dogs with an intact graft (IG) were more likely to have a successful outcome compared with dogs with a torn graft (P = .011). According to arthroscopy, 45% of grafts seemed to survive at 12 months after surgery.

CONCLUSION

About half of intra-articular allografts survived 12 months after implantation in CCL-deficient stifles. Dogs with IG had successful outcomes at 12 months after surgery according to assessment by force platform gait analysis.

CLINICAL SIGNIFICANCE

These results preclude immediate clinical application but provide evidence to justify further investigation of intra-articular grafts as a repair option for CLLD.

Network meta-analysis of knee outcomes following anterior cruciate ligament reconstruction with various types of tendon grafts

PURPOSE

Various grafts were selected for restoring knee stability and regaining pre-injury activity levels after anterior cruciate ligament (ACL) rupture. This review aimed to compare the short-term knee outcomes of different tendon grafts for primary ACL reconstruction (ACLR).

METHODS

Databases of PubMed, Embase, and CENTRAL were retrieved for identifying the published RCT comparing the short-term (≤ 2 years) knee outcomes of different tendon grafts for ACLR. The main outcomes include the International Knee Documentation Committee (IKDC) subjective and objective scores, side-to-side difference on knee laxity, Lachman test, pivot-shift test, Lysholm score, Tegner score, all recorded complications and graft re-ruptures.

RESULTS

A total of 32 trials involving 2962 patients and 17 grafts were included. Superior IKDC subjective score was found for quadriceps tendon autograft (QTB) when compared with autografts including bone-patellar tendon-bone (BPTB), four-strand hamstring tendon (4S-HT), and double-bundle HT. The 4S-HT autograft was associated with poorer anteroposterior and rotational knee stability than the BPTB autograft. Artificial ligament also was found to provide lower knee stability compared with the autografts including the BPTB, patellar tendon, 4S-HT, 4S-HT with preserved tibial insertion, 6S-HT, and four-strand semitendinosus tendon. Additionally, the BPTB allograft showed a statistically higher knee laxity than 6S-HT allograft, while no difference was found between the genuine autografts and non-irradiated allografts.

CONCLUSIONS

QTB was recommended to be used even over the BPTB and 4S-HT autografts. BPTB autograft was more effective on restoring the knee stability than 4S-HT autograft. Non-irradiated allografts could be safely used as alternatives to autografts. However, artificial ligaments were not recommended for primary ACLR for significantly increased risk of knee laxity.