Extensor mechanism function after patellar tendon graft harvest for anterior cruciate ligament reconstruction

Comparison of Knee Pain and Difficulty With Kneeling Between Patellar Tendon and Hamstring Tendon Autografts After Anterior Cruciate Ligament Reconstruction: A Study From the New Zealand ACL Registry

BACKGROUND

The bone-patellar tendon-bone (BTB) autograft is associated with difficulty with kneeling after anterior cruciate ligament (ACL) reconstruction; however, it is unclear whether it results in a more painful or symptomatic knee compared with the hamstring tendon autograft.

PURPOSE

To identify the rate and risk factors for knee pain and difficulty with kneeling after ACL reconstruction.

STUDY DESIGN

Cohort study; Level of evidence, 3.

METHODS

Primary ACL reconstruction procedures prospectively recorded in the New Zealand ACL Registry from April 2014 to May 2021 were analyzed. The Knee injury and Osteoarthritis Outcome Score (KOOS) was used to identify patients reporting consequential knee pain (CKP), defined as a KOOS Pain subscore of ≤72 points, and severe kneeling difficulty (SKD), defined as a self-report of "severe" or "extreme" difficulty with kneeling. Absolute values of the KOOS Pain and Symptoms subscales were also compared.

RESULTS

A total of 10,999 patients were analyzed. At 2-year follow-up, 9.3% (420/4492) reported CKP, and 12.0% (537/4471) reported SKD. The most important predictor of CKP at 2-year follow-up was having significant pain before surgery (adjusted odds ratio, 4.10; P < .001). The most important predictor of SKD at 2-year follow-up was the use of a BTB autograft rather than a hamstring tendon autograft (21.3% vs 9.4%, respectively; adjusted odds ratio, 3.12; P < .001). There was no difference between the BTB and hamstring tendon grafts in terms of CKP (9.9% vs 9.2%, respectively; P = .494) or in absolute values of the KOOS Pain (mean, 88.7 vs 89.0, respectively; P = .37) and KOOS Symptoms (mean, 82.5 vs 82.1, respectively; P = .49) subscales.

CONCLUSION

At 2-year follow-up after primary ACL reconstruction, 9.3% of patients reported CKP, and 12.0% reported SKD. The BTB autograft was associated with difficulty with kneeling, but it did not result in a more painful or symptomatic knee compared with the hamstring tendon autograft.

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.

Autograft and Nonirradiated Allograft for Anterior Cruciate Ligament Reconstruction Demonstrate Similar Clinical Outcomes and Graft Failure Rates: An Updated Systematic Review

Purpose

To perform an updated systematic review comparing the clinical outcomes of autograft versus nonirradiated allograft for anterior cruciate ligament reconstruction (ACLR).

Methods

A systematic review was conducted according to the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines by searching PubMed, the Cochrane Library, and Embase to identify comparative studies directly comparing outcomes of primary ACLR with autograft versus nonirradiated allograft with a minimum 2-year follow-up. The search terms used were: “anterior cruciate ligament” AND autograft AND allograft AND (irradiation OR non-irradiated). Patients were evaluated based on graft failure rates, the Objective International Knee Documentation Committee (IKDC) score, anteroposterior laxity, and patient-reported outcomes (Subjective IKDC score, the visual analog scale [VAS], the Cincinnati Knee Rating System, Lysholm, and Tegner scores). Risk of bias was assessed using the ROBINS-I and Cochrane Collaboration’s risk of bias tool for non-randomized and randomized studies, respectively.

Results

Sixteen studies (3 Level I, 7 Level II, 6 Level III) met inclusion criteria, including a total of 15,502 patients undergoing ACLR with autograft and 1,577 with nonirradiated allograft. The average follow-up ranged from 24.0 to 132.0 months. Graft failure ranged from 0% to 9.4% of patients in the autograft group and 0% to 26.5% in the allograft group. Two studies showed greater failure rates among younger patients in the allograft group. There were no significant differences between the Objective IKDC score, anteroposterior laxity, or patient-reported outcomes between the groups within any of the included studies (P > .05).

Conclusions

Autograft and nonirradiated allograft for primary ACLR demonstrate similar patient-reported outcomes and graft failure rates.

Level of Evidence

III, systematic review of level I-III studies.

Total Knee Arthroplasty after Anterior Cruciate Ligament Reconstruction

The incidence of anterior cruciate ligament (ACL) reconstruction is increasing in the United States, particularly in the older athlete. Patients who undergo ACL reconstruction are at higher risk for undergoing total knee arthroplasty (TKA) later in life. TKA in patients with prior ACL reconstruction has been associated with longer operative time due in-part to difficulty with exposure and retained hardware. Outcomes after TKA in patients with prior ACL reconstruction are not well defined, with some reports showing increased rate of complications and higher risk of reoperation compared with routine primary TKA, but these results are based on small and nonrandomized cohorts. Future research is needed to determine whether graft choice or fixation technique for ACL reconstruction influences outcomes after subsequent TKA. Furthermore, whether outcomes are affected by choice of TKA implant design for patients with prior ACL reconstruction warrants further study. This review analyzes the epidemiology, operative considerations, and outcomes of TKA following ACL reconstruction.

Quadriceps Strength following Anterior Cruciate Ligament Reconstruction: Normative Values based on Sex, Graft Type and Meniscal Status at 3, 6 & 9 Months

Background

Higher postoperative quadriceps function has been positively associated with surgical outcomes after anterior cruciate ligament reconstruction (ACLR). However, the impact of autograft harvest and/or a concomitant meniscal procedure on the recovery of quadriceps strength is not well defined.

Purpose

To describe postoperative recovery of quadriceps strength following ACLR related to autograft selection, meniscal status, and sex.

Study Design

Retrospective Cohort.

Methods

One hundred and twenty-five participants who underwent ACLR with either a hamstring tendon (HT), bone-patellar tendon-bone (BPTB) or quadriceps tendon (QT) autograft were included. At postoperative months 3, 6 and 9, each participant completed an isometric quadriceps strength testing protocol at 90-degrees of knee flexion. Participants' quadriceps average peak torque (Q-AvgPKT), average peak torque relative to body weight (Q-RPKT), and calculated limb symmetry index (Q-LSI) were collected and used for data analysis. Patients were placed in groups based on sex, graft type, and whether they had a concomitant meniscal procedure at the time of ACLR. At each time point, One-way ANOVAs, independent samples t-test and chi-square analyses were used to test for any between-group differences in strength outcomes.

Results

At three months after ACLR, Q-RPKT was significantly higher in those with the HT compared to the QT. At all time points, males had significantly greater Q-RPKT than females and HT Q-LSI was significantly higher than BPTB and QT. A concomitant meniscal procedure at the time of ACLR did not significantly affect Q-LSI or Q-RPKT at any testing point.

Conclusion

This study provides outcomes that are procedure specific as well as highlights the objective progression of quadriceps strength after ACLR. This information may help better-define the normal recovery of function, as well as guide rehabilitation strategies after ACLR.

Level of Evidence

3.

Patellar Tendon Orientation and Strain Are Predictors of ACL Strain In Vivo During a Single-Leg Jump

BACKGROUND

There is little in vivo data that describe the relationships between patellar tendon orientation, patellar tendon strain, and anterior cruciate ligament (ACL) strain during dynamic activities. Quantifying how the quadriceps load the ACL via the patellar tendon is important for understanding ACL injury mechanisms.

HYPOTHESIS

We hypothesized that flexion angle, patellar tendon orientation, and patellar tendon strain influence ACL strain during a single-leg jump. Specifically, we hypothesized that patellar tendon and ACL strains would increase concurrently when the knee is positioned near extension during the jump.

STUDY DESIGN

Descriptive laboratory study.

METHODS

Models of the femur, tibia, ACL, patellar tendon, and quadriceps tendon attachment sites of 8 male participants were generated from magnetic resonance imaging (MRI). High-speed biplanar radiographs during a single-leg jump were obtained. The bone models were registered to the radiographs, thereby reproducing the in vivo positions of the bones, ligament, and tendon attachment sites. Flexion angle, patellar tendon orientation, patellar tendon strain, and ACL strain were measured from the registered models. ACL and patellar tendon strains were approximated by normalizing their length at each knee position to their length at the time of MRI. Two separate bivariate linear regression models were used to assess relationships between flexion angle and patellar tendon orientation and between ACL strain and patellar tendon strain. A multivariate linear regression model was used to assess whether flexion angle and patellar tendon strain were significant predictors of ACL strain during the inflight and landing portions of the jump.

RESULTS

Both flexion angle and patellar tendon strain were significant predictors (P < .05) of ACL strain. These results indicate that elevated ACL and patellar tendon strains were observed concurrently when the knee was positioned near extension.

CONCLUSION

Concurrent increases in patellar tendon and ACL strains indicate that the quadriceps load the ACL via the patellar tendon when the knee is positioned near extension.

CLINICAL RELEVANCE

Increased ACL strain when the knee is positioned near extension before landing may be due to quadriceps contraction. Thus, landing with unanticipated timing on an extended knee may increase vulnerability to ACL injury as a taut ligament is more likely to fail.

Determinants of regeneration and strength of hamstrings after anterior cruciate ligament reconstruction-fate of hamstring tendon

BACKGROUND AND AIM

Arthroscopic reconstruction of anterior cruciate ligament (ACL) surgical procedure using hamstring autograft is the most common surgery performed in the arena of sports medicine and arthroscopy. Most studies in literature are ambiguous regarding the fate of hamstrings based on function, regenerative potential, and cross-sectional area (CSA). The aim of this research study is analysis of the fate of hamstring tendons (both semitendinosus and gracilis) during the time course for determinants of regeneration and strength.

METHODS

Fifty patients who were operated for unilateral isolated ACL reconstruction from July 2015 to June 2018 were evaluated for the fate of harvested hamstring tendons which included the following: regeneration, cross-sectional area (CSA), strength, and insertion of regenerated hamstrings by isometric torque and isokinetic strength. MRI of knee was performed for both knees concerning the semitendinosus (ST), gracilis (G), Sartorius, biceps femoris, and medial head of gastrocnemius.

RESULTS

Eighty-four percent men and 16% women within a mean patient age of 34 ± 4.12 years were evaluated and all 50 (100%) patients demonstrated hamstring regeneration by the MRI measurements at six months and at one year post-ACL reconstruction. The torque of isometric knee flexion measured in 60° was found to be remarkably lower in the ACL-reconstructed lower extremity compared to that of the contralateral limb (87.13 ± 20.18% of BW), at 90° (49.17 ± 15.09% BW), and at 105° (43.91 ± 13.17% BW), respectively (p < 0.01). However, at 30° flexion and 45° flexion, the difference was insignificant (116.48 ± 21.07% BW for 30° and 100.16 ± 25.12% BW for 45°).

CONCLUSIONS

It was found that the properties of musculotendinous units of ST and G were significantly transformed after their harvesting for ACL reconstruction and these weaknesses contribute to the flexion deficit of knee in the deeper range of flexion in the operated limb. Therefore, approaches facilitating tendon regeneration and preservation must be warranted.

A SYSTEMATIC REVIEW OF THE EFFECTS OF BLOOD FLOW RESTRICTION TRAINING ON QUADRICEPS MUSCLE ATROPHY AND CIRCUMFERENCE POST ACL RECONSTRUCTION

Background

ACL reconstruction often results in an extended period of muscle atrophy and weakness. Blood flow restriction (BFR) training is a technique that has been shown to decrease muscle atrophy in a variety of populations.

Purpose

The purpose of this systematic review was to analyze the research presented on the effect of blood flow restriction training on quadriceps muscle atrophy and circumference post ACL reconstruction.

Study Design

Systematic Review.

Methods

Articles were reviewed using the databases Google Scholar, PubMed, and EBSCO. Keywords included blood flow restriction training, ACL reconstruction, and quadriceps.

Inclusion criteria included

English language, peer-reviewed journals; randomized control trials; and articles including blood flow restriction and measurement of quadriceps atrophy and circumference post ACL reconstruction. Exclusion criteria included non-English language publications; studies without a control group; and articles without sufficient data to evaluate the methodology. Four studies met the selection criteria and were assessed using the GRADE scale, which analyzes the strength of a study based on study limitations, precision, consistency, directness, and publication bias. After a GRADE designation was assigned, the following information was extracted from and compared across the studies: participant demographics, cuff used, graft used during ACL reconstruction, tool used to assess muscle atrophy, protocol used, and conclusions.

Results

Three out of four studies showed some amount of an increase in femoral muscle cross sectional area after the use of BFR combined with low-intensity resistance training (LIRT). The strength of all four studies was moderate when assessed using the GRADE scale.

Conclusion

This review of the available evidence yields promising results regarding the use of BFR and LIRT in the remediation of femoral muscle atrophy after an ACL reconstruction. Further research is necessary before BFR can be recommended for use in clinical settings.

Level of evidence

3a.

Does Blood Flow Restriction Training Improve Quadriceps Measures After Arthroscopic Knee Surgery? A Critically Appraised Topic

Focused Clinical Question: Is there evidence to suggest that blood flow restriction (BFR) training improves strength, cross-sectional area, and thigh girth of the quadriceps musculature in patients after arthroscopic surgical procedures of the knee? Clinical Bottom Line: There is moderate consistent, but low-level, evidence supporting the use of BFR training to improve knee extensor muscular outcomes (strength, cross-sectional area, and/or thigh girth) immediately after arthroscopic knee surgery.

All inside full thickness quadriceps tendon ACL reconstruction: Long term follow up results

Purpose

The aim of this study is to evaluate results of anterior cruciate ligament reconstruction (ACL) using an All-Inside Full Thickness Quadriceps Reconstruction technique at 5 years follow up.

Methods

This is a Retrospective cohort study of patients undergoing ACL reconstruction. Inclusion criteria for this report were isolated primary ACL reconstructions without chondral lesions (Grade III/IV Outerbridge), using autologous full-thickness quadriceps tendon (FQT) graft with bone block, with an “all-inside” technique. Functional scales of Lysholm, IKDC, Tegner and objective results of side to side difference (KT1000) were used for this evaluation. Additionally, complications and comorbidities were also analyzed.

Results

Two hundred and ninety-one ACL reconstructions were retrospectively reviewed at 5 years postoperatively; 268 (92.1%) were men and 23 (7.90%) women. Lysholm Score improved from 64 (SD = 6.09) to 91 (SD = 6.05) points average. IKDC showed 59.79%, excellent and 3.4% good results. Arthrometric analysis showed that 259 knees (89%) had a difference of less than 3 mm. Median pre-injury Tegner score was 9 (Range 4–10), while final median Tegner activity level at 5 years was 8 (Range 4–10). Among comorbidities, 5.15% of the patients presented anterior knee pain. No visualization difficulties or significant hematomas were found.

Conclusion

Use of all inside FQT for ACL reconstruction in a young, high demand sports population, present at 5 years, good to excellent results, functionally and objectively, with low rates of complications and comorbidities.

Quadriceps Muscle Size Following ACL Injury and Reconstruction: A Systematic Review

Image-based assessments of quadriceps muscle size facilitate examination of structural changes after anterior cruciate ligament (ACL) injury and reconstruction (ACLR). Understanding the effects of ACLR on muscle size measures may aid in clarifying the contribution of quadriceps atrophy toward quadriceps strength. The purpose of this study was to systematically review the literature examining the effects of ACLR on quadriceps muscle volume and cross-sectional area (CSA). An online database search was conducted using Web of Science, SportDISCUS, PubMed (Medline), CINHAL (EBSCO), and Cochrane Library limited to articles published after January 1, 1980. Means and standard deviations were extracted for the ACLR limb and the contralateral limb, and sample characteristics from relevant articles. Magnitude of between limb differences were assessed using pooled effect sizes (Hedge's g) and 95% confidence intervals. Eleven articles (five CSA, six muscle volume) were included in this systematic review. Included studies reported negative effective sizes, indicating that the ACLR limb was smaller in CSA or muscle volume compared with the contralateral limb; however, 36% of the included articles reported meaningful difference between the limbs. Quadriceps atrophy may occur following ACL injury and persist after rehabilitation, however, the magnitude of these reductions may not be clinically meaningful and may only partially explain the persistent quadriceps weakness that is ubiquitous among this patient population. © 2019 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 38:598-608, 2020.

Effect of Graft Choice on Revision and Contralateral Anterior Cruciate Ligament Reconstruction: Results From the New Zealand ACL Registry

BACKGROUND

The patellar tendon is often considered the "gold standard" graft for reducing the risk of graft rupture after anterior cruciate ligament (ACL) reconstruction. However, its use may also be associated with an increased risk of injury to the contralateral ACL.

PURPOSE

To clarify the association between graft choice and the risk of revision and contralateral ACL reconstruction.

STUDY DESIGN

Cohort study; Level of evidence, 2.

METHODS

Prospective data captured by the New Zealand ACL Registry between April 2014 and December 2018 were reviewed. All primary ACL reconstructions performed using either a hamstring tendon or patellar tendon autograft were included. Cox regression survival analysis adjusting for patient factors was performed to compare the risk of revision and contralateral ACL reconstruction between the hamstring tendon graft and the patellar tendon graft.

RESULTS

A total of 7155 primary ACL reconstructions were reviewed, of which 5563 (77.7%) were performed using a hamstring tendon graft and 1592 (22.3%) were performed using a patellar tendon graft. Patients with a hamstring tendon graft had a revision rate of 2.7% compared with 1.3% in patients with a patellar tendon graft (adjusted hazard ratio [HR], 2.51; 95% CI, 1.55-4.06; P < .001). The patellar tendon graft was associated with an increased risk of contralateral ACL reconstruction compared with the hamstring tendon graft (adjusted HR, 1.91; 95% CI, 1.15-3.16; P = .012). The number needed to treat (NNT) with a patellar tendon graft to prevent 1 revision was 73.6. However, the NNT with a hamstring tendon graft to prevent 1 contralateral reconstruction was 116.3.

CONCLUSION

Use of a patellar tendon graft reduced the risk of graft rupture but was associated with an increased risk of injury to the contralateral ACL. Adequate rehabilitation and informed decision making on return to activity and injury prevention measures may be important in preventing subsequent injury to the healthy knee.

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.

Superior knee flexor strength at 2 years with all-inside short-graft anterior cruciate ligament reconstruction vs a conventional hamstring technique

PURPOSE

To compare the "all-inside technique" for anterior cruciate ligament (ACL) reconstruction using a short, quadrupled semitendinosus tendon (ST4) autograft and suspensory cortical fixation on both the femoral and tibial side vs the "conventional technique" using a semitendinosus/gracilis (ST/G) autograft fixed with a suspensory device on the femoral side and with an interference screw on the tibial side, in terms of clinical and functional outcomes.

METHODS

A total of 90 patients were enrolled, randomised into two groups, and prospectively followed. Group A comprised 45 patients treated with the all-inside technique and Group B included 45 patients treated with the conventional ACL technique (55 males, 35 females; mean age 28.7 ± 11.3 years). Patients completed the Lysholm knee score, the International Knee Documentation Committee (IKDC) score, the Knee Injury and Osteoarthritis Score (KOOS), and the Knee Society Score (KSS) preoperatively and at 2 years postoperatively. Anterior tibial translation measurement (KT-1000 arthrometer) and isokinetic testing of the operative vs non-operative limb were also conducted and the limb symmetry index (LSI) was determined.

RESULTS

At 24 months, the Lysholm, IKDC, KOOS, and KSS scores between the two groups were similar (n.s.). Anterior tibial translation between the operative and non-operative knee was also similar among the two groups (n.s.). Patients of Group A had significantly higher mean LSIs in terms of flexor peak torque (1.0 ± 0.1 vs 0.9 ± 0.1; p < 0.001), time-to-peak (0.9 ± 0.1 vs 0.8 ± 0.1; p < 0.001) and total work (0.9 ± 0.1 vs 0.8 ± 0.1; p < 0.001) at 180°/s, and significantly better mean LSI for isometric flexor/extensor ratio at 90° (1.1 ± 0.3 vs 0.8 ± 0.2; p < 0.001).

CONCLUSION

The all-inside ACL reconstruction with an ST4 autograft and cortical button fixation on both ends is a viable alternative to the conventional technique. It affords preservation of knee flexor strength, which is of advantage, especially when treating athletes with ACL injury.

LEVEL OF EVIDENCE

I.

Hamstring Braid Graft Technique for Anterior Cruciate Ligament Reconstruction

Hamstring autograft is one of the most used grafts for anterior cruciate ligament (ACL) reconstruction, although there are several graft preparation techniques. It is extremely difficult to mimic the biomechanical properties of the native ACL; thus, it is important to achieve a proper graft configuration, diameter, and length. To avoid reruptures, an optimal and reproducible hamstring autograft is desired. Hamstring autograft has been traditionally devalued when compared with other options such as bone-patellar tendon-bone autograft. The purpose of this Technical Note is to describe in detail a hamstring braid graft configuration that could potentially overcome the past disadvantages of ACL reconstruction.

Advanced Patellar Tendinopathy Is Associated With Increased Rates of Bone-Patellar Tendon-Bone Autograft Failure at Early Follow-up After Anterior Cruciate Ligament Reconstruction

Background

Revision anterior cruciate ligament (ACL) reconstruction can be potentially devastating for a patient. As such, it is important to identify prognostic factors that place patients at an increased risk for graft failure. There are no data on the effects of patellar tendinopathy on failure of ACL reconstruction when using a bone-patellar tendon-bone (BPTB) autograft.

Purpose/Hypothesis

The purpose of this study was to investigate the association of patellar tendinopathy with the risk of graft failure in primary ACL reconstruction when using a BPTB autograft. The hypothesis was that patellar tendinopathy would result in higher rates of graft failure when using a BPTB autograft for primary ACL reconstruction.

Study Design

Cohort study; Level of evidence, 3.

Methods

All patients undergoing ACL reconstruction at a single institution from 2005 to 2015 were examined. A total of 168 patients undergoing primary ACL reconstruction with a BPTB autograft were identified. Patients' magnetic resonance imaging scans were reviewed for the presence and grade of patellar tendinopathy by 2 musculoskeletal fellowship-trained radiologists; both were blinded to the aim of the study, patient demographics, surgical details, and outcomes. Patients were divided into 2 groups: failure (defined as presence of symptomatic laxity or graft insufficiency) and success of the ACL graft. Statistical analyses were run to examine the association of patellar tendinopathy with failure of ACL reconstruction using a BPTB autograft.

Results

At a mean follow-up of 18 months, there were 7 (4.2%) patients with graft failure. Moderate or severe patellar tendinopathy was associated with ACL graft failure (P = .011). Age, sex, and side of reconstruction were not associated with the risk of graft failure, although the majority of patients who failed were younger than 20 years. The use of patellar tendons with moderate to severe tendinopathy was associated with a relative risk of ruptures of 6.1 (95% CI, 1.37-27.34) as compared with autograft tendons without tendinopathy.

Conclusion

Moderate or severe patellar tendinopathy significantly increases the risk of graft failure when using a BPTB autograft for primary ACL reconstruction. Patellar tendinopathy should be considered when determining the optimal graft choice for patients undergoing primary ACL reconstruction with autograft tendons.

Superior return to sports rate after patellar tendon autograft over patellar tendon allograft in revision anterior cruciate ligament reconstruction

PURPOSE

After revision anterior cruciate ligament reconstruction (ACLR), the rate of return to the pre-injury type of sport (RTS type) is low and graft choice might be an important factor. The aim of this study was to determine whether there is a difference in outcome after revision ACLR using a patellar tendon allograft compared to an ipsilateral patellar tendon autograft. It was hypothesized that the rate of RTS type using an ipsilateral patellar tendon autograft will be superior to using patellar tendon allograft.

METHODS

The design is a retrospective cohort study. Inclusion criteria were patients who underwent revision ACLR with a minimum follow-up of 1 year after revision using a patellar allograft or ipsilateral autograft. Primary study parameter was rate of RTS type. Secondary study parameters were RTS level, subscores of the KOOS, the IKDC_subjective, the Tegner score and reasons for no RTS.

RESULTS

Eighty-two patients participated in this study (36 allografts and 46 autografts). In patients with a minimum follow-up of 1 year, rate of RTS type was 51.4% for the patellar tendon allograft and 62.8% for the patellar tendon autograft group (n.s.). In patients with a minimum follow-up rate of 2 years, rate of RTS type was 43.3 versus 75.0%, respectively (p = 0.027). No differences in secondary study parameters were found. In patients with a minimum follow-up of 1 year, rate of RTS type was significantly higher (p = 0.025) for patients without anxiety compared to patients who were anxious to perform certain movements.

CONCLUSION

After a minimum follow-up of 2 years, rate of RTS type is in favour of using an ipsilateral patellar tendon autograft when compared to using a patellar tendon allograft in patients undergoing revision ACLR; after a minimum follow-up of 1 year, no significant difference was found. In revision ACLR, the results of this study might influence graft choice in favour of autologous graft when the use of an allograft or autograft patellar tendon is considered.

LEVEL OF EVIDENCE

III.

Higher hamstring-to-quadriceps isokinetic strength ratio during the first post-operative months in patients with quadriceps tendon compared to hamstring tendon graft following ACL reconstruction

PURPOSE

The aim of this study was to compare isokinetic quadriceps and hamstring muscle strength in patients following anterior cruciate ligament (ACL) reconstruction who received either hamstring (HT) or quadriceps (QT) tendon autografts at two time intervals within the first year after surgery.

METHODS

One hundred twenty-four patients, 81 males (age 22.0 ± 6.2 years) and 43 females (age 20.9 ± 8.7 years), participated in this study. ACL reconstruction was performed with either quadriceps tendon autografts (QT; n = 61) or hamstring tendon autografts (HT; n = 63). Two isokinetic muscle strength tests (t1: 5.5 ± 1.2 months; t2: 7.6 ± 1.6 months) were performed at an angular velocity of 60°/s in both the injured and contralateral knees. An independent t test as well as a two-factor analysis of variance with repeated measurements was used. The significance level was set at p < 0.05.

RESULTS

A statistically significant lower knee extensor strength was observed in the QT group within one year after surgery (p < 0.001). Additionally, data showed a significant higher H/Q ratio in QT patients compared to the HT group at t1 (p < 0.001) and t2 (p = 0.001) as well as a significant effect over time (p < 0.001) and interaction effect of time and graft (p = 0.007). Side-to-side values for extensor muscle strength were significantly (p < 0.001) greater in HT graft patients, while QT patients showed significantly (p < 0.001) greater values for flexor muscle strength at both time points of isokinetic testing, respectively.

CONCLUSION

The results of this study indicate that graft choice has an impact on extensor strength in the first months after ACL reconstruction; however, there is no impact on flexor strength. The finding of a higher H/Q ratio in patients with QT grafts within the first months following surgery is possibly of clinical relevance. This may potentially be associated with lower stress on the maturing ACL graft. Furthermore, normal thigh strength can be restored over time.

LEVEL OF EVIDENCE

III.

Arthroscopic ACL reconstruction using patellar bone tendon autograft and Rigidfix fixation - A midterm functional outcome

Background

Arthroscopic reconstruction of torn Anterior Cruciate Ligament (ACL) with bone patellar tendon bone autograft (BTB) has become the gold standard in treating ACL tear with high success rate. The purpose of this study was to prospectively evaluate the functional outcome after arthroscopic ACL reconstruction using BTB via Rigidfix femoral fixation.

Materials and method

We evaluated the result of 21 knees that have been treated with arthroscopic ACL reconstruction using BTB autograft for femoral fixation and bioabsorbable interference screw for tibia from March 2014 to August 2015. The mean follow up period was 18 months.

Results and conclusion

The Lysholm score postoperatively was 89.04. 23.8% of the 21 patients have good to excellent outcome, 66.7% patients have good to fair outcome and 9.5% patient have fair outcome.

Level of Evidence

IV.

Increased Risk of Revision After Anterior Cruciate Ligament Reconstruction With Soft Tissue Allografts Compared With Autografts: Graft Processing and Time Make a Difference

BACKGROUND

The optimal graft for anterior cruciate ligament reconstruction (ACLR) remains controversial.

PURPOSE

To compare the risk of aseptic revision between bone-patellar tendon-bone (BPTB) autografts, hamstring autografts, and soft tissue allografts.

STUDY DESIGN

Cohort study; Level of evidence, 2.

METHODS

Prospectively collected ACLR cases reconstructed with BPTB autografts, hamstring autografts, and soft tissue allografts were identified using the Kaiser Permanente ACLR Registry. Aseptic revision was the endpoint. The type of graft and allograft processing method (nonprocessed, <1.8-Mrad irradiation with and without chemical processing [Allowash or AlloTrue], ≥1.8-Mrad irradiation with and without chemical processing, and chemical processing alone [BioCleanse]) were the exposures evaluated. Analyses were adjusted for age, sex, and race. Kaplan-Meier curves and Cox proportional hazards models were employed.

RESULTS

The cohort included 14,015 cases: there were 8924 (63.7%) male patients, there were 6397 (45.6%) white patients, 4557 (32.5%) ACLRs used BPTB autografts, 3751 ACLRs (26.8%) used soft tissue allografts, and 5707 (40.7%) ACLRs used hamstring autografts. The median age was 34.6 years for soft tissue allografts, 24.3 years for hamstring autografts, and 22.0 years for BPTB autografts. The crude nonadjusted revision rates were 85 (1.9%) in BPTB autograft cases, 132 (2.3%) in hamstring autograft cases, and 83 (2.2%) in soft tissue allograft cases. After adjusting for age, sex, and race, compared with hamstring autografts, a higher risk of revision was found with allografts with ≥1.8 Mrad without chemical processing after 2.5 years (hazard ratio [HR], 3.88; 95% CI, 1.48-10.12) and ≥1.8 Mrad with chemical processing after 1 year (HR, 3.43; 95% CI, 1.58-7.47) and with BioCleanse processed grafts at any time point (HR, 3.02; 95% CI, 1.40-6.50). Nonprocessed allografts and those irradiated with <1.8 Mrad with or without chemical processing were not found to have a different risk of revision compared with hamstring autografts. Compared with BPTB autografts, a higher risk of revision was seen with hamstring autografts (HR, 1.51; 95% CI, 1.15-1.99) and BioCleanse processed allografts (HR, 4.67; 95% CI, 2.15-10.16). Allografts irradiated with <1.8 Mrad with chemical processing (Allowash or AlloTrue) (HR, 2.19; 95% CI, 1.42-3.38) and without chemical processing (HR, 2.31; 95% CI, 1.40-3.82) had a higher risk of revision, as did allografts with ≥1.8 Mrad without chemical processing after 2 years (HR, 6.30; 95% CI, 3.18-12.48) and ≥1.8 Mrad with chemical processing (Allowash or AlloTrue) after 1 year (HR, 5.03; 95% CI, 2.30-11.00) compared with BPTB autografts. Nonprocessed allografts did not have a higher risk of revision compared with autografts. With the numbers available, direct comparisons between the specific allograft processing methods were not possible.

CONCLUSION

When soft tissue allografts are used for ACLR, processing and time from surgery affect the risk of revision. Tissue processing has a significant effect on the risk of revision surgery, which is most profound with more highly processed grafts and increases with increasing follow-up time. Surgeons and patients need to be aware of the increased risks of revision with the various soft tissue allografts used for ACLR.

Primary anterior cruciate ligament reconstruction: perioperative considerations and complications

Anterior cruciate ligament (ACL) injuries are among the most commonly studied orthopaedic injuries. Despite having an excellent prognosis, complications do occur. The timely recognition and management of complications is imperative to ensure the success of reconstruction. Avoiding such complications requires thorough preoperative planning, proficient technical skills to properly manage intraoperative complications, and an extensive knowledge of possible postoperative complications.

Evaluation of the site specificity of acute disuse muscle atrophy developed during a relatively short period in critically ill patients according to the activities of daily living level: A prospective observational study

INTRODUCTION

In critically ill patients, excessive bed rest and immobilisation have been shown to cause disuse muscle atrophy, which contributes to prolonged hospitalisation and decreased activity of daily living (ADL) levels. However, the degree and site specificity of acute disuse muscle atrophy in critically ill patients during a relatively short intensive care unit (ICU) stay have not been fully elucidated.

METHODS

Critically ill patients, who required bed rest on ICU admission, were eligible for this study. The degree of skeletal muscle atrophy was evaluated on the day of, and 72 and 144h after ICU admission by measuring the limb circumference in ADL-dependent or -independent patients separately at five different sites: the midpoint of the upper limb between the acromion and the olecranon, the maximum diameter of the triceps surae in the lower leg, and three different sites in the thigh at 5, 10, and 15cm above the superior pole of the patella. Value of the limb circumference was presented as a percentage relative to the baseline (median).

RESULTS

In ADL-dependent patients, limb circumferences at all five sites were decreased significantly at 144h compared with the baseline (98.9-100% in the upper limbs, 97.1-97.2% in the lower legs, and 96.5-99.1% in the thighs), but not at 72h. In contrast, the limb circumferences at almost all sites decreased significantly at both 72 and 144h (100% in the upper limbs, 94.5-94.7% in the lower legs, and 89.7-94.7% in the thighs), compared with the baseline in ADL-independent patients. Muscle atrophy was greater at the four different lower-limb sites compared to the upper limb during 144h in the ICU in the ADL-independent, but not in the ADL-dependent patients.

CONCLUSIONS

Compared to ADL-dependent patients, ADL-independent patients are prone to develop muscle weakness, especially in the lower limbs.

Extensor tendon ruptures after total knee arthroplasty

Extensor tendon rupture is a rare but serious complication after total knee arthroplasty (TKA) that impairs active knee extension, thereby severely affecting knee function. Surgery is usually required. Surgical options range from simple suturing to allograft reconstruction of the entire extensor mechanism and include intermediate methods such as reconstruction using neighbouring tendons or muscles, synthetic ligament implantation, and partial allograft repair. Simple suturing carries a high failure rate and should therefore be routinely combined with tissue augmentation using a neighbouring tendon or a synthetic ligament. After allograft reconstruction, outcomes are variable and long-term complications common. Salvage procedures for managing the most severe cases after allograft failure involve reconstruction using gastrocnemius or vastus flaps. Regardless of the technique used, suturing must be performed under tension, with the knee fully extended, and rehabilitation must be conducted with great caution. Weaknesses of available case-series studies include small sample sizes, heterogeneity, and inadequate follow-up duration. All treatment options are associated with substantial failure rates. The patient should be informed of this fact and plans made for a salvage option. Here, the main techniques and their outcomes are discussed, and a therapeutic strategy is suggested.

RECONSTRUCTION OF THE ANTERIOR CRUCIATE LIGAMENT WITH THE CENTRAL THIRD OF THE QUADRICEPS MUSCLE TENDON: ANALYSIS OF 10-YEAR RESULTS

Objective: Assess clinical results using two different protocols, 10 years after ACL reconstruction surgery with the central third of quadriceps muscle tendon (QT). Method: Between November /1997 and April/1998, 25 patients were submitted to 25 ACL reconstructions with QT by transtibial technique. The bone portion of the graft was fixated on femoral tunnel with interference screw and the tendinous portion of tibial tunnel with screw with washer. Two patients injured the new when playing soccer. Six patients were not available for follow-up (24%). Seventeen patients were evaluated, 15 men and two women, with mean age at surgery time of 28.53 ± 6.64 years. All patients were examined at six months, one year, and ten years after surgery. Clinical evaluation was made by the Lysholm scale, and the knee evaluation, with the Hospital for Special Surgery scale. Results: The patients had their injuries operated after 9.87 ± 14.42 months of the accident. According to Lysholm scale, the results at the end of the first year were 98.71 ± 2.47 and, after 10 years, 97.35 ± 3.12. Using the Hospital for Special Surgery scale, the mean score was 95.07 ± 5.23 in one year, and 94.87 ± 4.16 in 10 years. All patients returned to their professional activities with the same previous status. Fifteen (88.24%) patients were able to return to their sports activities, one by modifying the practice, while another one switched to another sport. No patient complained of pain on the donor area in the medium and long term. The sports return rate was excellent, and no changes were found on the femoropatellar joint.

Revision Risk After Allograft Anterior Cruciate Ligament Reconstruction: Association With Graft Processing Techniques, Patient Characteristics, and Graft Type

BACKGROUND

Allograft tissue is a common graft choice for anterior cruciate ligament reconstruction (ACLR). Allograft sterilization methods vary widely across numerous commercial tissue vendors. Multiple studies, despite being limited in sample size, have suggested a higher rate of clinical failure associated with the use of allograft tissue in ACLR when compared with autograft.

PURPOSE

To examine the association of graft processing techniques, patient characteristics, and graft type with risk of revision surgery after allograft ACLR.

STUDY DESIGN

Cohort study; Level of evidence, 3.

METHODS

A retrospective cohort study was conducted that used an integrated United States health care system's ACLR registry to identify primary unilateral cases in which allografts were used. Aseptic revision was the endpoint of the study. Allograft type, processing methods (irradiation dose, AlloWash, AlloTrue, BioCleanse), and graft donor age were assessed as potential risk factors for revision, with adjustment for patient age, sex, and body mass index (BMI) by use of survival analysis. Hazard ratios (HR) and 95% confidence intervals (CIs) were calculated.

RESULTS

A total of 5968 primary ACLR cases with allograft were included in the study, of which 3688 (61.8%) were male patients. The median age of the cohort at the time of surgery was 34.1 years (interquartile range, 24.1-42.9 years). The mean time to follow-up (±SD) was 2.1 ± 1.5 years. There were 3751 (62.9%) allograft ACLRs using soft tissue, 1188 (19.9%) with Achilles tendon, and 1029 (17.2%) with bone-patellar tendon-bone (BPTB). Graft processing groups included BioCleanse (n = 367), AlloTrue or AlloWash (n = 2278), irradiation greater than 1.8 Mrad (n = 1146), irradiation up to 1.8 Mrad (n = 3637), and no irradiation (n = 1185). There were 156 (2.6%) aseptic revisions. After adjustment for patient age, sex, and BMI, the use of BioCleanse (HR = 2.45; 95% CI, 1.36-4.40) and irradiation greater than 1.8 Mrad (HR = 1.64; 95% CI, 1.08-2.49) were associated with a higher risk of revision when compared with all other methods of processing. BPTB allografts were at higher risk of revision (HR = 1.79; 95% CI, 1.20-2.66) when compared with soft tissue allografts. Conversely, with every 5-year increase in age, the risk of revision was 0.67 (95% CI, 0.61-0.73) times lower. Male patients were found to be at higher risk of revision when compared with females (HR = 1.47; 95% CI, 1.04-2.07). The use of AlloWash or AlloTrue processing, patient BMI, and graft donor age did not affect revision rate significantly.

CONCLUSION

In the largest known study of its kind examining outcome after primary allograft ACLR, graft irradiation greater than 1.8 Mrad, BioCleanse graft processing, younger patient age, male patients, and BPTB allograft were all associated with a higher risk of clinical failure and subsequent revision surgery.

Femoral quadriceps neuromuscular electrical stimulation after total knee arthroplasty: a systematic review

The purpose of this study was to evaluate the effects of neuromuscular electrical stimulation in patients submitted to total knee arthroplasty. This was a systematic review with no language or publication status restriction. Our search was made in Cochrane Library, MEDLINE, Embase and LILACS. Randomized or quasi-randomized clinical trials evaluating neuromuscular electrical stimulation after total knee arthroplasty were included. Four studies with moderate risk of bias and low statistical power were included, totalizing 376 participants. There was no statistically significant difference in knee function, pain and range of motion during 12 month follow-up. This review concluded that neuromuscular electrical stimulation was less effective than traditional rehabilitation in function, muscular strength and range of motion. However, this technique was useful for quadriceps activation during the first days after surgery.

Unstable elbow dislocations: the description and cadaveric feasibility study of a new surgical technique

Introduction: A small proportion of simple elbow dislocations are grossly unstable and joint congruence is not maintained after reduction. In this rare situation operative treatment is indicated. We describe a new intra articular reconstruction that utilises a slip of triceps tendon to provide immediate stability to the elbow.

Methods: We assessed 20 cadaveric elbows, measuring the length of triceps tendon available and required to complete the reconstruction. We then sequentially sectioned the ligamentous stabilisers of an elbow before performing the new technique. We measured the displacement and angulation possible at the elbow before and after the reconstruction.

Results: All 20 elbows had sufficient triceps tendon length to complete the new technique. Prior to the reconstruction greater than 30 mm of joint distraction and 90 degrees varus or valgus angulation was possible. Following the reconstruction it was not possible to re-dislocate the elbow. Only 2 mm of joint distraction and 10 degrees of varus or valgus angulation were possible with the triceps graft fixed in position.

Discussion: This novel technique elegantly avoids many of the problems associated with current methods. We have demonstrated that it is technically feasible and easy to perform with minimal equipment requirements or costs.

Hamstring Tendon Regeneration After Harvest for Anterior Cruciate Ligament Reconstruction: A Systematic Review

PURPOSE

To assess whether the portions of the semitendinosus and gracilis tendons harvested for anterior cruciate ligament reconstruction have the potential to regenerate and, if so, to evaluate the histologic properties and actual function of this newly formed tissue.

METHODS

We performed a comprehensive search of CINAHL (Cumulative Index to Nursing and Allied Health Literature), Embase, Medline, the Cochrane Central Registry of Controlled Trials, and SPORTDiscus from inception of the databases to July 2014, using various combinations of keywords. Studies focusing on hamstring tendon and muscle regeneration through imaging and histology, as well as on the related functional outcomes, were selected. We included studies assessing evidence of tissue regeneration with imaging (magnetic resonance imaging, 3-dimensional computed tomography, ultrasonography) or with histologic examination of biopsy samples (or a combination thereof).

RESULTS

Nineteen articles were included in this review, with a total of 400 patients observed. The overall rate of tissue regeneration was 86.0%, with similar values shown in most studies regardless of the methodology of the assessment. Biopsy confirmed that the tissue found at the site in 74% of the cases showed typical histologic features of the tendon. The mean modified Coleman Methodology Score of the studies included was 52.7 points, showing a modest methodologic quality for the studies published to date.

CONCLUSIONS

In over 85% of the cases analyzed, regeneration signs of the harvested tendon were found through different imaging and histologic methodologies. A torque deficit in deep knee flexion is always present postoperatively, but the cause for this is still unclear. There is a need for better-designed trials featuring a higher level of evidence to further investigate this matter, and the effects of postoperative care and the surgical approach used on the regeneration process should be analyzed in the future.

LEVEL OF EVIDENCE

Level IV, systematic review of Level II, III, and IV studies.

Serial changes in knee muscle strength after anterior cruciate ligament reconstruction using hamstring tendon autografts

PURPOSE

The purpose of this study was to evaluate serial changes in quadriceps and hamstring muscle strength over the first postoperative year in patients who underwent anterior cruciate ligament (ACL) reconstruction with an autologous hamstring tendon graft and to reveal which of these 2 muscles lost more strength and recovered more slowly after autologous hamstring ACL reconstruction.

METHODS

Isokinetic muscle strength was measured preoperatively and at 6 months and 1 year postoperatively in 20 patients who underwent ACL reconstruction. The maximal torque (60°/s) and total work (180°/s) of the quadriceps and hamstring were evaluated using an isokinetic testing device. The isokinetic muscle strength and endurance of the injured legs were expressed as percentages of those of the uninjured legs at the same time point.

RESULTS

Both quadriceps and hamstring muscle strength at 60°/s and endurance at 180°/s of the injured relative to the uninjured leg was 50% preoperatively. Quadriceps muscle strength and endurance of the injured leg increased to 70% at 6 months and 80% at 1 year postoperatively, whereas hamstring muscle strength and endurance increased to 80% at 6 months and 80% at 1 year.

CONCLUSIONS

Knee muscle strength recovered progressively after ACL reconstruction using autologous hamstring tendons but did not fully recover, being about 80% that of the uninjured leg even 1 year after surgery.

LEVEL OF EVIDENCE

Level IV, therapeutic case series.

Factors associated with excellent 6-month functional and isokinetic test results following ACL reconstruction

PURPOSE

To identify patient concomitant injury and surgical characteristics associated with 6-month excellent functional and isokinetic testing results following anterior cruciate ligament (ACL) reconstruction.

METHODS

Patients that underwent ACL reconstruction by a single surgeon had isokinetic and functional testing performed with excellent 6-month outcome defined as greater than 85 % in isokinetic strength and 90 % in functional tests (excellent 6-month group vs. delayed 6-month group). Patient concomitant injury and surgical factors were then analysed in univariate and multivariate statistical models to assess which characteristics predicted the excellent 6-month group.

RESULTS

The 224 patients included 93 males and 131 females, with median age of 22 (range 12-59) years, body mass index (BMI) of 25.4 (range 17-44), and median Tegner activity score of 6 (range 2-10). Fifty-two patients (23 %) were included in the excellent 6-month group, while 172 patients (77 %) were in the delayed 6-month group. In univariate analysis, favourable factors with the excellent 6-month outcome group were younger age (24 vs. 27; p = 0.01), lower BMI (24.5 vs. 26.2; p = 0.03), and minimal articular cartilage damage (71 vs. 56 %; p = 0.048). In multivariate analysis, a negative effect was observed for patients older than 30 years that had ACL reconstruction with autograft (p = 0.0004).

CONCLUSION

Factors significantly associated with excellent 6-month functional and isokinetic test results following ACL reconstruction included younger age, lower BMI, and minimal cartilage degeneration. The use of allograft was associated with improved functional and strength testing after ACL reconstruction in patients over 30 years of age.

LEVEL OF EVIDENCE

Prognostic/therapeutic study, Level III.

Closure of patellar tendon defect in anterior cruciate ligament reconstruction with bone-patellar tendon-bone autograft: systematic review of randomized controlled trials

PURPOSE

This study aimed to systematically review the highest level of evidence on anterior cruciate ligament (ACL) reconstruction with bone-patellar tendon-bone (BPTB) autografts with patellar tendon defect closure versus no closure after surgery.

METHODS

We performed a systematic review of multiple medical databases using Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. Level I and Level II randomized controlled trials comparing patellar tendon defect closure to no closure during ACL reconstruction with BPTB autografts were included. Two independent reviewers analyzed all studies. Descriptive statistics were calculated. Study methodological quality was analyzed using the Modified Coleman Methodology Score (MCMS) and Jadad scale.

RESULTS

Four studies with a combined 221 patients (154 male patients and 67 female patients) with an average age of 26.6 ± 2.4 years (range, 17 to 54 years) were included. All studies randomized patients before surgery into ACLR with BPTB autografts either with patellar tendon defect closure or without closure. There were no differences in clinical outcomes (Lysholm score, Tegner scale, International Knee Documentation Committee [IKDC] classification, modified Larsen score, and Lauridsen rating) between groups. There were no significant differences in knee pain between groups. All studies reported imaging findings of the patellar tendon defect, with 2 studies showing no difference in appearance between groups, one study showing excessive scar formation with defect repair, and one study showing improved restoration of normal tendon appearance with defect repair. The overall quality of the studies was poor, with all studies scoring less than 46 (average, 40.5 ± 4.7) on the MCMS and scoring 1 on the Jadad scale.

CONCLUSIONS

Based on this systematic review of 4 randomized trials, there are no statistically significant or clinically relevant differences in outcomes between patients who have the patellar tendon defect closed and those who have it left open after ACLR with BPTB autografts. The methodology of the included studies limits the interpretation of the data, as evidenced by low MCMS and Jadad scores.

LEVEL OF EVIDENCE

Level II, systematic review of Level I and Level II studies.

Functional Performance Testing After Anterior Cruciate Ligament Reconstruction: A Systematic Review

Background:

When to allow an athlete to return to unrestricted sporting activity after anterior cruciate ligament (ACL) reconstruction remains controversial.

Purpose:

To report the results of functional performance testing reported in the literature for individuals at differing time points following ACL reconstruction and to examine differences between graft types.

Study Design:

Systematic review; Level of evidence, 4.

Methods:

A systematic review of Medline, Scopus, and Cochrane Central Register of Controlled Trials was performed using PRISMA guidelines. Inclusion criteria were English-language studies that examined any functional rehabilitation test from 6 months to 2 years following ACL reconstruction. All patient-, limb-, and knee-specific demographics were extracted from included investigations. All functional rehabilitation tests were analyzed and compared when applicable.

Results:

The search term returned a total of 890 potential studies, with 88 meeting inclusion and exclusion criteria. A total of 4927 patients were included, of which 66% were male. The mean patient age was 26.5 ± 3.4 years. The predominant graft choices for reconstruction were bone–patellar tendon–bone (BPTB) autograft (59.8%) and hamstring autograft (37.9%). The most commonly reported functional tests were the hop tests. The results of these functional tests, as reported in the Limb Symmetry Index (LSI), improved with increasing time, with nearly all results greater than 90% at 1 year following primary ACL reconstruction. At 6 months postoperatively, a number of isokinetic strength measurements failed to reach 80% LSI, most commonly isokinetic knee extension testing in both BPTB and hamstring autograft groups. The knee flexion strength deficit was significantly less in the BPTB autograft group as compared with those having hamstring autograft at 1 year postoperatively, while no significant differences were found in isokinetic extension strength between the 2 groups.

Conclusion:

Hop testing was the most commonly reported functional test following ACL reconstruction. Increases in performance on functional tests were predictably seen as time increased following surgery. Those with hamstring autografts may experience increased strength deficits with knee flexion versus those having BPTB autograft. These data provide information that may assist providers in determining timing of return to unrestricted sporting activity.

Compact platelet-rich fibrin scaffold to improve healing of patellar tendon defects and for medial collateral ligament reconstruction

BACKGROUND

Platelets are one of the most biocompatible and cost-effective sources of growth factors. Attention is being paid to autologous platelets and platelet-rich plasma. We developed a novel compact platelet-rich fibrin scaffold (CPFS) that was produced from blood and calcium gluconate only. The objective of this study was to investigate the potential of CPFS as a provisional scaffold in two rabbit models.

METHODS

In the first rabbit model, the central half of the patellar tendon was resected bilaterally. Allogenic CPFS was attached to the defect in the right knee, while the left knee was untreated. In the other model, the medial collateral ligament was removed bilaterally. The ligament of the right knee was reconstructed with allogenic CPFS, whereas the left knee was untreated.

RESULTS

After 12weeks, the ultimate failure load and stiffness were higher for the right patellar tendon than for the left patellar tendon in the former model. It was found that CPFS promoted ligament repair tissue in contrast with that on the untreated side in the latter model. The ultimate failure load of the CPFS repair tissue at 20weeks was 78% of that in healthy controls of the same age.

CONCLUSIONS

CPFS enhanced the healing of tendons and ligaments.

CLINICAL RELEVANCE

CPFS has the potential to accelerate healing of tendons and ligaments as a provisional bioscaffold or a material for graft augmentation.

Semitendinosus muscle fatty infiltration following tendon harvest in rabbits

The hamstring tendon autograft is one of the most commonly used graft choices in Anterior cruciate ligament (ACL) reconstruction. There are conflicting results regarding postoperative hamstring strength deficits in patients who have had a hamstring graft. The semitendinosus tendon has been shown to regenerate after harvesting for ACL autograft, suggesting that the muscle has the potential to regain normal function. However, no studies have been performed to define the microstructural changes that occur in the semitendinosus muscle after tendon resection. In this study, we hypothesized that fatty infiltration of the semitendinosus muscle after tendon harvest in New Zealand White rabbits increases postoperatively and remains constant or increases during the first year of repair. The semitendinosus tendon was unilaterally detached and harvested from 15 rabbits. Five rabbits were sacrificed at 3-, 6-, and 12-month intervals, and the semitendinosus muscle-tendon units were analyzed. The contralateral unoperated limb served as the control. The gross tendon and muscle dimensions and histologic percentage of fatty infiltration were measured. We found no significant difference in fatty infiltration at any time point between the control muscle and test specimens and that there was no progression of fatty infiltration over time. If these results hold true in humans, natural repair of the hamstring muscle following tendon harvest during ACL autograft reconstruction is not inhibited by fatty infiltration.

Anterior cruciate ligament reconstruction with autografts compared with non-irradiated, non-chemically treated allografts

PURPOSE

Allograft anterior cruciate ligament (ACL) reconstruction obviates donor site morbidity and may accelerate postoperative recovery. However, allograft use can lead to increased rates of surgical failure, particularly when chemical processing or irradiation is used. Few studies have rigorously evaluated the comparative outcomes of autografts and fresh-frozen allograft tissue for ACL reconstruction.

METHODS

We performed a PubMed search to identify and systematically evaluate outcomes of autograft and non-chemically treated non-irradiated allograft tissue in ACL reconstruction between 1980 and 2012. We included studies with Level of evidence of I to III, determinate graft treatment, a minimum of 25 patients per treatment arm, a minimum 2-year follow-up, and selected subjective and objective outcome measures.

RESULTS

After the exclusion of 585 citations, we isolated 11 studies for further review. All patients showed improvement in clinical outcome measures and knee stability end points from injury to definitive surgical management. No statistically significant differences were detected between autografts and non-chemically processed non-irradiated allografts in Lysholm scores, International Knee Documentation Committee (IKDC) scores, Lachman examinations, pivot-shift testing, KT-1000 measurements, or failure rates.

CONCLUSIONS

Further large-scale, well-designed studies are required to better evaluate the comparative outcomes after fresh-frozen allograft ACL reconstruction. The current study suggests that the results after autograft ACL reconstruction are comparable to those using non-chemically processed nonirradiated allograft tissue.

LEVEL OF EVIDENCE

Systematic review of Level I to III studies.

Cryopreservation with glycerol improves the in vitro biomechanical characteristics of human patellar tendon allografts

PURPOSE

To evaluate the in vitro biomechanical characteristics of patellar tendon ligaments (BTB) when stored as fresh frozen or as glycerol cryopreserved allografts.

METHODS

Seventy patellar tendons were harvested from 35 cadaveric human donors and randomly assigned into seven groups. Grafts in group FRESH were mechanically tested within 2 h of harvesting. FROZ-3, FROZ-6, and FROZ-9 were deep-frozen to -80 °C for 3, 6, and 9 months, respectively. Grafts in groups CRYO-3, CRYO-6, and CRYO-9 were initially incubated with 10% glycerol in a phosphate-buffered saline for 1 h and then stored in glycerol solution (10% glycerol in PBS) at -80 °C for 3, 6, and 9 months, respectively. Grafts were mechanically tested with two cycling modes (50-250 °N and 150-500 °N) and then loaded to failure.

RESULTS

Cryopreserved grafts demonstrated more consistent results and expressed lower elongation rates after both cycling loading protocols compared to their frozen counterparts at all storage times. During load-to-failure analysis, ultimate stiffness levels were predominantly higher (23.9-61.5%) in cryopreserved grafts compared with frozen grafts, and ultimate stress levels were 26% (13.3-47.7%) higher, regardless of the storage time. Moreover, cryopreserved grafts revealed similar ultimate elongation and uniformly higher ultimate stiffness and ultimate stress levels compared to fresh grafts.

CONCLUSION

The results of this in vitro study demonstrated superior mechanical properties of cryopreserved grafts compared to frozen grafts within a preservation period of 9 months. Cryopreservation with glycerol solution might be used to further improve the quality of preserved soft-tissue allografts.

The use of eccentrically biased resistance exercise to mitigate muscle impairments following anterior cruciate ligament reconstruction: a short review

Background:

Novel interventions that can safely and effectively overload muscle early following anterior cruciate ligament reconstruction are needed to minimize atrophy and weakness that often becomes longstanding.

Evidence Acquisition:

Eccentrically induced forces can be safely applied during the early stages of rehabilitation following surgery and serve as a potent stimulus for increasing muscle size and strength.

Results:

Compared to a standard rehabilitation program, adding an early 12-week eccentric resistance-training program 3 weeks after anterior cruciate ligament reconstruction induces improvement in quadriceps and gluteus maximus volume at 15 weeks and at 1 year after surgery. Likewise, those who performed an eccentrically biased rehabilitation program also achieved greater improvements in quadriceps strength and hopping ability measured at 15 weeks and at 1 year after surgery.

Clinical Relevance:

There is potential to safely and feasibly perform eccentric contractions as part of a formal rehabilitation program following anterior cruciate ligament reconstruction.

Donor-site-related functional problems following anterior cruciate ligament reconstruction: development of a self-administered questionnaire

PURPOSE

To develop a self-administered questionnaire for the evaluation of donor-site-related functional problems after anterior cruciate ligament (ACL) reconstruction with autograft harvested from the hamstring tendon or patellar tendon and to determine the content validity, reliability and preliminary factor structure of this new instrument.

METHODS

Seven physiotherapists with long clinical experience of rehabilitation after ACL reconstruction and 60 patients from the target population participated as experts in the developmental stages of the questionnaire. Content validity was determined and quantified with the content validity index (CVI). Test-retest reliability, internal consistency and factor structure were evaluated in another 64 patients reconstructed with an autograft.

RESULTS

The final questionnaire included 16 items on symptoms and function during activities of daily living and exercise. Excellent content validity on both item level (I-CVI ≥ 0.83, range 0.83-1.00) and scale level (S-CVI = 0.93) was found. The test-retest reliability was good, ICC = 0.94. Internal consistency was high, and Cronbach's α was 0.92 and 0.94 at each test occasion. The principal components analysis yielded a four-component structure.

CONCLUSIONS

The questionnaire "Donor-site-Related Functional Problems following Anterior Cruciate Ligament (ACL) Reconstruction" is a patient-reported questionnaire with high content validity and reliability for the evaluation of donor-site-related functional problems after ACL reconstruction, with autograft harvested from the hamstring tendon or patellar tendon. The results of this study support the use of this questionnaire as a standardized outcome measure for both research purposes and in clinical settings.

Evaluation and treatment of disorders of the infrapatellar fat pad

The infrapatellar fat pad (IFP), also known as Hoffa's fat pad, is an intracapsular, extrasynovial structure that fills the anterior knee compartment, and is richly vascularized and innervated. Its degree of innervation, the proportion of substance-P-containing fibres and close relationship to its posterior synovial lining implicates IFP pathologies as a source of infrapatellar knee pain. Though the precise function of the IFP is unknown, studies have shown that it may play a role in the biomechanics of the knee or act as a store for reparative cells after injury. Inflammation and fibrosis within the IFP, caused by trauma and/or surgery can lead to a variety of arthrofibrotic lesions including Hoffa's disease, anterior interval scarring and infrapatellar contracture syndrome. Lesions or mass-like abnormalities rarely occur within the IFP, but their classification can be narrowed down by radiographical appearance. Clinically, patients with IFP pathology present with burning or aching infrapatellar anterior knee pain that can often be reproduced on physical exam with manoeuvres designed to produce impingement. Sagittal MRI is the most common imaging technique used to assess IFP pathology including fibrosis, inflammation, oedema, and mass-like lesions. IFP pathology is often successfully managed with physical therapy. Passive taping is used to unload or shorten an inflamed IFP, and closed chain quadriceps exercises can improve lower limb control and patellar congruence. Training of the gluteus medius and stretching the anterior hip may help to decrease internal rotation of the hip and valgus force at the knee. Gait training and avoiding hyperextension can also be used for long-term management. Injections within the IFP of local anaesthetic plus corticosteroids and IFP ablation with ultrasound guided alcohol injections have been successfully explored as treatments for IFP pain. IFP pathology refractory to physical therapy can be approached through a variety of operative treatments. Arthroscopic partial resection for IFP impingement and Hoffa's disease has showed favourable results; however, total excision of the IFP performed concomitantly with total knee arthroplasty (TKA) resulted in worse results when compared with TKA alone. Arthroscopic debridement of IFP fibrosis has been successfully used to treat extension block following anterior cruciate ligament reconstruction, and arthroscopic anterior interval release has been an effective treatment for pain associated with anterior interval scarring. Arthroscopic resection of infrapatellar plicae and denervation of the inferior pole of the patella have also been shown to be effective treatments for refractory infrapatellar pain.

Anterior cruciate ligament reconstruction with bone-patellar tendon-bone graft: comparison of autograft, fresh-frozen allograft, and γ-irradiated allograft

PURPOSE

To compare clinical follow-up results of anterior cruciate ligament (ACL) reconstruction using (1) autologous, (2) fresh-frozen allogeneic, and (3) γ-irradiated allogeneic bone-patellar tendon-bone (BPTB).

METHODS

From February 2002 to January 2006, 187 patients received BPTB ACL reconstruction at our center. One hundred forty-two consecutive patients who had received single-bundle BPTB ACL reconstruction were included in this study. Of these patients, 41 had autografts, 33 had fresh-frozen allografts, and 68 had γ-irradiated allografts. Clinical results were evaluated with the KT-1000 maximum displacement test (MEDmetric, San Diego, CA), Lachman test, and Lysholm, Irrgang, and Larson activity scales.

RESULTS

The mean duration of follow-up was 6.7 ± 1.5 years (range, 4.2 to 8.2 years). There were 3 cases of acute synovitis due to immunologic rejection (fresh-frozen allografts) and 6 cases of failure (γ-irradiated allografts). KT-1000 examination showed more anterior laxity in the γ-irradiated allograft group compared with the autograft and fresh-frozen allograft groups (P < .05). The Lysholm, Irrgang, and Larson activity scales showed no difference among the 3 groups (P > .05).

CONCLUSIONS

The study showed a statistically poorer KT-1000 result and higher failure rate in the γ-irradiated allograft group compared with the autograft and fresh-frozen allograft groups. This may suggest that γ-irradiated allograft is not a good candidate graft for ACL reconstruction. Power analysis showed that the study was underpowered, so further research and longer follow-up study are needed to make this point clearer.

LEVEL OF EVIDENCE

Level III, retrospective comparative study.

Anatomic single bundle anterior cruciate ligament reconstruction by the two anteromedial portal method: the comparison of transportal and transtibial techniques

Purpose

The purpose of this study was to report the results of anatomic single bundle anterior cruciate ligament (ACL) reconstruction by the two anteromedial portal method.

Materials and Methods

We evaluated the clinical results in 33 patients with ACL rupture who were treated by anatomic ACL reconstruction using the two anteromedial portal technique. The control group included 33 patients with ACL rupture who were treated with the conventional transtibial non-anatomic method. We performed an objective instability test, both preoperatively and at the final follow-up. We also compared the clinical results of both groups using International Knee Documentation Committee and Lysholm scores as a subjective test.

Results

At the final follow up, the study showed that in the control group, the Lachman test was negative in 27 cases (81.8%), the pivot shift test was negative in 26 cases (78.8%), and the average anterior translocation was 3.1 mm on a KT-2000 arthrometer. In the group of patients who underwent anatomic reconstruction by the two anteromedial portal method, the Lachman test was negative in 28 cases (84.8%), the pivot shift test was negative in 30 cases (90.9%), and the average anterior translocation was 2.8 mm on the KT-2000 arthrometer. Results in the pivot shift showed statistically significant improvement compared to the control group.

Conclusions

Anatomic ACL reconstruction by two anteromedial portals is an effective surgical technique that restores the rotational stability with excellent clinical results.

Model predictions of increased knee joint loading in regions of thinner articular cartilage after patellar tendon adhesion

Patellar tendon adhesion is a complication from anterior cruciate ligament (ACL) reconstruction that may affect patellofemoral and tibiofemoral biomechanics. A computational model was used to investigate the changes in knee joint mechanics due to patellar tendon adhesion under normal physiological loading during gait. The calculations showed that patellar tendon adhesion up to the level of the anterior tibial plateau led to patellar infera, increased patellar flexion, and increased anterior tibial translation. These kinematic changes were associated with increased patellar contact force, a distal shift in peak patellar contact pressure, a posterior shift in peak tibial contact pressure, and increased peak tangential contact sliding distance over one gait cycle (i.e., contact slip). Postadhesion, patellar and tibial contact locations corresponded to regions of thinner cartilage. The predicted distal shift in patellar contact was in contrast to other patellar infera studies. Average patellar and tibial cartilage pressure did not change significantly following patellar tendon adhesion; however, peak medial tibial pressure increased. These results suggest that changes in peak tibial cartilage pressure, contact slip, and the migration of contact to regions of thinner cartilage are associated with patellar tendon adhesion and may be responsible for initiating patellofemoral pain and knee joint structural damage observed following ACL reconstruction.

[Reconstruction of anterior cruciate ligament by using two different techniques]

INTRODUCTION

Modern literature concerning reconstructions of Anterior Cruciate Ligament is mostly focused on the choice of graft (hamstring or bone-tendon-bone), its placing, tensioning and fixation. The bone-hamstring-bone graft consists of compressed cancellous bone on its ends and it has been developed to achieve a more rigid fixation of the graft. The aim of this study was to compare the postoperative results in surgically treated patients two years after the reconstruction of anterior cruciate ligament.

MATERIAL AND METHODS

The study included 55 patients divided into two groups according to the implanted graft: bone-tendon-bone and bone-hamstring-bone graft. The results were assessed by Tegner and Lysholm scoring systems, arthrometric measurements, functional tests and International Knee Documentation Committee standard.

RESULTS

The average postoperative results did not show a statistically significant difference (p < 0.05) between the two groups (94 in the bone-tendon-bone group versus 93 in the bone-hamstring-bone group) according to Lysholm scoring system, nor in the arthrometric measurements obtained by Lachman test (2.0:2.1). According to the International Knee Documentation Committee standard, the bone-hamstring-bone group had more excellent results, but also three unsatisfactory ones; so, the bone-tendon-bone group was found to have uniform and better results (100% of excellent and good results vs. 91% in the bone-hamstring-bone group). Better results were also recorded by Tegner scoring system in the bone-tendon-bone group (8.6 vs. 7.1) due to the fact that there were more active athletes and greater preoperative level of activities in this group (3.1 vs. 7.1 in the bone-hamstring group).

CONCLUSIONS

The choice of graft is a less important factor in the reconstruction of anterior cruciate ligament than its placing, tensioning and fixation, because a significant difference between groups was recorded only by the International Knee Documentation Committee standard.

Does Vitamin E and C Supplementation Improve the Recovery From Anterior Cruciate Ligament Surgery?

Muscular (quadriceps) weakness is a predominant impairment that follows anterior cruciate ligament injury and surgery. This continued weakness impairs activities of daily living and could predispose patients to adverse conditions later in life, such as knee osteoarthritis. Vitamins E and C have potent antioxidant and anti-inflammatory activity. Herein, the authors summarize the state-of-the science and suggest directions for future research endeavors regarding the therapeutic influence of vitamins E and C, or other antioxidants, on the recovery from anterior cruciate ligament injury and surgery.