Time to treat the tendon rupture induced by surgery: early hypertrophy of the patellar tendon graft site predicts strong quadriceps after ACLR with bone-patellar tendon-bone autograft

PURPOSE

Quadriceps dysfunction is ubiquitous after anterior cruciate ligament reconstruction, especially when using bone-patellar tendon-bone (BPTB) autografts. The role of patellar tendon hypertrophy after graft harvest on knee extensor strength is unknown. The purpose of this study was to determine the predictive ability of patellar tendon (PT) and quadriceps muscle (Quad) cross-sectional area (CSA) on knee extensor strength 1-2 months after ACLR using BPTB autografts.

METHODS

This is a cross-sectional analysis of a cohort 1-2 months after ACLR using BPTB autograft. Peak knee extensor torque, and PT and Quad CSA measured using ultrasound imaging, were collected in 13 males and 14 females. Simple linear regressions compared quadriceps strength index (QI) against limb symmetry index (LSI) in PT and Quad CSA. Multiple linear regressions with sequential model comparisons predicting peak knee extensor torque were performed for each limb. The base model included demographics. Quad CSA was added in the first model, then PT CSA was added in the second model.

RESULTS

Both PT (p < 0.001, R2 = 0.693) and Quadriceps CSA (p = 0.013, R2 = 0.223) LSI had a positive linear relationship with QI. In the involved limb, addition of PT CSA significantly improved the model (R2 = 0.781, ΔR2 = 0.211, p for ΔR2 < 0.001). In the uninvolved limb, the addition of Quad CSA improved the model, but the addition of PT CSA did not.

CONCLUSION

PT LSI was more predictive of QI than Quad CSA LSI. Involved limb PT CSA mattered more in predicting peak knee extensor torque than did Quad CSA, but in the uninvolved limb, Quad CSA was the most important predictor of peak knee extensor torque. Graft site patellar tendon hypertrophy is key for strong quadriceps early after ACLR. Early targeted loading via exercise to promote healing of the graft site patellar tendon may bring patients a step closer to winning their battle against quadriceps dysfunction.

LEVEL OF EVIDENCE

Level I.

[The Use of BTB Allograft in Revision Reconstruction of the Anterior Cruciate Ligament and Its Success Rate in Terms of Subjective Patient Satisfaction]

PURPOSE OF THE STUDY A retrospective evaluation of the success rate of revision ACL reconstruction performed using BTB allograft in terms of the life expectancy of the procedure up to and over five years from surgery. MATERIAL AND METHODS Over a ten-year period, from 2003 to 2013, we performed 47 revision ACL reconstruction surgeries. The majority of the primary ACL reconstructions using BTB autografts were not performed at our site. The group observed included 16 women (34%) and 31 men (66%). The women were aged between 25 and 48 years, the median age being 32.5, and the men were aged between 25 and 46 years with the median age of 35. We were able to make a full pre- and post-operative evaluation of 22 out of 47 patients who underwent secondary ACL reconstruction surgery using a cadaverous BTB graft. This evaluation included an objective clinical testing and a subjective evaluation of the function and stability of the knee joint using the Tegner activity score, Lysholm score, and a modified Cincinatti score. The set of 22 patients was split into two groups: up to five years from revision surgery and over five years from the procedure. RESULTS In the group of patients who were fully evaluated within five years of revision reconstruction there was an average improvement of 16.4 points on the Cincinatti score, 19.9 points on the Lysholm score, and an upward movement averaging 1.5 levels on the Tegner activity score. In the over five years from surgery category the average improvement was 15.5, 15.9, and 1.2 levels upward movement, respectively. We were unable to prove a significantly increased level of failure in BTB allografts after five and more years from revision ACL reconstruction. DISCUSSION The two strongest factors affecting the life expectancy of ACL replacements are the age of the patient and the type of the graft used, allograft or autograft. The most at risk, in terms of how long the graft will last, is the age group of 10 - 19 years old. With each ten-year increase in age the risk of rupture is reduced more-or-less by half. Patients with ACL allograft replacement show a fourfold increased risk of the graft rupturing. The younger and more active the patient requiring revision ACL reconstruction is, the greater the need for an autograft. If an allograft has been used in revision reconstruction on an athlete, a great emphasis must be placed on the necessity of delaying the return to previous sporting activities for at least nine months. CONCLUSIONS The mid-term results of revision ACL reconstruction show that, subject to reasonable levels of stress, a correctly performed procedure using cadaverous BTB grafts is a good option to restore the stability of the knee joint over a period of five years and more from surgery. An increased incidence of reruptures or greater insufficiency of the cadaverous graft were not evident in our group after five and more years. The risk of cadaverous grafts failure is just like in the autologous replacement directly linked to the return to sport interval, frequency and intensity of stress to which the graft is subjected over a long period of time. The risk of rerupture is always higher in allograft reconstructions that have already stood in need of restructuring for a longer period of time. For this reason, a delay in returning to sports activity must be emphasized. As a rule, we recommend a return to full athletic training only after nine months to a year after surgery. Key words: anterior cruciate ligament, revision ACL reconstruction, tendon graft insufficiency, BTB autograft insufficiency, BTB allograft of the ACL, cadaverous BTB graft, ACL graft rerupture.

Tibial Tubercle Fracture After Bone-Patellar Tendon-Bone Autograft

Fractures occurring with anterior cruciate ligament (ACL) reconstruction are rare and those that do occur take place on the patellar side of a bone-patellar tendon-bone (BPTB) autograft. Here we discuss a far more infrequent occurrence, fracture of the tibial tubercle aspect of the BPTB autograft. This fracture type occurs even more infrequently than tibial plateau fractures after ACL reconstruction based on the published literature. In this article we discuss the third published episode of a tibial tubercle fracture after BPTB allograft. We also discuss the fracture types seen with this method of ACL reconstruction and provide insights into prevention of this occurrence.

Does sequence of graft tensioning affect outcomes in combined anterior and posterior cruciate ligament reconstructions?

BACKGROUND

Controversy persists regarding the protocol for tensioning and securing the grafts in one-stage reconstruction of combined anterior cruciate ligament (ACL) and posterior cruciate ligament (PCL) injuries. Many authors have reported stability examinations and functional results after reconstruction for this relatively rare injury, and the best sequence for tensioning the grafts is not known.

QUESTIONS/PURPOSES

We sought to determine (1) if there are differences in postoperative anteroposterior stability in a protocol of simultaneous tensioning of both grafts and ACL-first fixation compared with a protocol of tensioning and fixation of the PCL first in one-stage reconstruction of combined ACL/PCL injuries; and (2) if there is a difference in postoperative functional outcome scores between the two protocols.

METHODS

Between 2001 and 2011, 29 patients underwent one-stage reconstruction of combined ACL and PCL injuries (the majority with medial collateral ligament [MCL] injuries, posterolateral corner [PLC] injuries, or both, in addition), of whom three patients (10%) were lost to followup before 2 years, and one patient was excluded based on predefined criteria, leaving a total of 25 patients (86%) for retrospective analysis in this report. Fourteen patients underwent one-stage reconstruction of these injuries with tensioning and fixation of the PCL graft first (PCL-first group), and 11 later patients underwent one-stage reconstruction of combined ACL/PCL injuries with simultaneous tensioning of both grafts and fixation of the ACL graft first (simultaneous-tensioning group). During the period in question, the technique used in the PCL-first group was used exclusively for these injuries between August 2001 and August 2008 and that used in the simultaneous-tensioning group was used between September 2008 and August 2011; there was no overlap between groups. The groups were similar in terms of demographics and length of followup. Each patient was assessed for associated injuries, preoperative and postoperative knee stability with anteroposterior stress radiographs, and was evaluated with the Lysholm knee score and International Knee Documentation Committee (IKDC) subjective and objective grading at the last followup after surgery.

RESULTS

At the last followup evaluation, patients treated with simultaneous tensioning and ACL-first fixation showed less instability on side-to-side difference of posterior stress radiography (5±1 mm in the simultaneous-tensioning group versus 6±1 mm in the PCL-first group; effect size, 1.2; 95% confidence interval [CI], 0.5-2.3; p=0.011), but with the numbers available, no difference on anterior stress radiography (3±0.4 mm in the simultaneous-tensioning group versus 3±0.5 mm in PCL-first group; effect size, 0.4; 95% CI, -0.2 to 0.5; p=443). The simultaneous-tensioning group also had higher Lysholm knee scores (87±5 in the simultaneous-tensioning group versus 80±4 in the PCL-first group; effect size, 1.8; 95% CI, -10.9 to -2.7; p=0.001), IKDC subjective scores (68±3 in the simultaneous-tensioning group versus 58±3 in the PCL-first group; effect size, 3.4; 95% CI, -14.2 to -8.6; p<0.001), and IKDC objective grades (p=0.037).

CONCLUSIONS

In one-stage reconstruction of combined ACL and PCL injuries, a protocol of simultaneous tensioning both grafts and fixing the ACL graft first may be worth consideration. Arthroscopic reduction landmarks may prove helpful in this technique but require further validation.

LEVEL OF EVIDENCE

Level III, therapeutic study. See Guidelines for Authors for a complete description of levels of evidence.

Fracture of the patella after the anterior cruciate ligament reconstruction

INTRODUCTION

Fracture of the patella, after harvesting the central third of the patellar tendon for a bone-tendon-bone autograft, is a rare complication.

MATERIAL AND METHODS

We made 1714 reconstructions of the anterior cruciate ligament of the knee using bone-patellar tendon-bone technique, and 7 patients had fracture of the patella (0.42%). The fracture was immediately recognized in the patients with vertical non-displaced patellar fracture and the broken screw osteosynthesis was carried out without changes in the rehabilitation period. One patient was treated non-operatively and patellar fracture in four patients was treated with operative reduction and osteosynthesis.

RESULTS

The patients were invited for the check-up 5 years (2-8 years) after surgery on average. The mean Lysholm score was 92 (85-100). All of them continued to engage in sporting activities at the same or greater level after 9 months on average (6-12 months). In all patients the Lachman test was with the firm stop compared to the other leg. X-ray changes in the patella were found in 2 patients who had multifragmentary fractures.

DISCUSSION AND CONCLUSION

The fracture of patella can be prevented by avoiding to take too much bone graft, by using the most precise tools for cutting, while rehabilitation must be carefully planned. The optimal treatment of the fracture of the patella after the reconstruction of the anterior cruciate ligament is a firm osteosynthesis, which allows healing of the bone and continuation of the rehabilitation program.

Clinics in diagnostic imaging. 141. Complete anterior cruciate ligament tear

A 38-year-old man presented with right knee pain and swelling following a football injury. Magnetic resonance (MR) imaging showed a complete anterior cruciate ligament (ACL) tear and lateral meniscal tears. The torn ACL was repaired with a graft obtained from the semitendinosus muscle, and the menisci were debrided. The mechanisms of injury to the ACL are varied and may be due to direct or indirect contact with the knee as well as with twisting injuries. Knowledge of the ACL's normal anatomy, together with MR imaging technique and understanding of the appearance of the lesion on MR examination, is crucial to aid in the identification of an ACL tear. Diagnosis of an ACL tear should be based on direct MR imaging signs, although indirect signs may be helpful, particularly in chronic tears. Other associated injuries to be aware of include meniscal and other ligamentous injuries. Normal ACL graft and post-ACL graft reconstruction complications are also briefly discussed.

Knee function and prevalence of osteoarthritis after isolated anterior cruciate ligament reconstruction using bone-patellar tendon-bone graft: long-term follow-up

PURPOSE

The aim of this investigation was to study patient-reported long-term clinical outcome, instrumental stablitity and prevalence of radiological osteoarthritis (OA) a minimum of ten years after isolated anterior cruciate ligament (ACL) reconstruction.

METHODS

An average of 13.5 years after ACL reconstruction with bone-patellar tendon-bone (BTB) autograft, 73 patients were evaluated. Inclusion criteria consisted of an isolated ACL rupture and reconstruction with BPTB graft with no associated intra-articular lesions, in particular, cartilage alterations or meniscal lesions. Clinical assessment was performed using the International Knee Documentation Committee (IKDC) and Tegner and Lysholm scores. Instrumental anterior laxity testing was carried out with the KT-1000™ arthrometer. Degree of degenerative changes and prevalence of OA were determined using the Kellgren- Lawrence scale.

RESULTS

Mean follow-up was 13.5 years. Mean age was 43.8 years. About 75% of patients were graded A or B according to the IKDC score. The Lysholm score was 90.2 ± 4.8. Radiological assessment reported degenerative changes of grade II OA in 54.2% of patients. Prevalence of grades III or IV OA was found in 20%. The incidence of OA was significantly correlated with stability and function at long-term follow-up.

CONCLUSION

Arthroscopic ACL reconstruction using BPTB autograft resulted in a high degree of patient satisfaction and good clinical results on long-term follow-up. A higher degree of OA developed in 20% of patients and was significantly correlated with increased anterior laxity at long-term follow-up.

Intra-articular lateral femoral condyle fracture following an ACL revision reconstruction

Lateral femoral condyle fractures following an ACL reconstruction are rare. To our knowledge, this is the first case report of a lateral femoral condyle fracture following a revision ACL reconstruction. The patient's fracture was intra-articular, had a significant amount of soft tissue damage, and was further complicated by a large defect involving the bone tunnel from the ACL revision reconstruction. The patient was treated with an open reduction and internal fixation and recovered well.

A 2-year follow-up of rehabilitation after ACL reconstruction using patellar tendon or hamstring tendon grafts: a prospective randomised outcome study

Sixty-eight patients were clinically evaluated preoperatively, 3, 5, 7, 9 months, 1 and 2 years after ACL reconstruction, 34 with patellar tendon graft, 34 with hamstring graft. Outcome regarding graft choice and anterior knee laxity (P = 0.04) was in favour of patellar tendon graft. Hamstring graft led to a larger laxity, 2.4 mm compared with patellar tendon graft, 1.3 mm at 1 year and 2.5 mm and 1.5 mm, respectively, at 2 years (P = 0.05). There was a significant difference in rotational knee stability in favour of the patellar tendon graft at all test occasions but 9 months. A general effect regarding graft choice and muscle torque was found at 90 degrees/s for quadriceps (P = 0.03) and hamstrings (P < or = 0.0001) and at 230 degrees/s for hamstrings (P < or = 0.0001). No treatment effect regarding graft choice and one-leg hop test, postural sway or knee function was found. No group differences in anterior knee pain were found at any of the test occasions but 2 years in favour of hamstring graft compared to patellar tendon graft (P = 0.04). Patellar tendon graft resulted in higher activity level than hamstring graft at all test occasions but 1 year (P = 0.01). Patellar tendon ACL reconstruction led to more stable knees with less anterior knee laxity and less rotational instability than hamstring ACL reconstruction. Hamstring graft patients had not reached preoperative level in hamstring torque even 2 years after ACL reconstruction. Athletes with patellar tendon graft returned to sports earlier and at a higher level than those with hamstring graft.

Inferior tendon graft to bone tunnel healing at the tibia compared to that at the femur after anterior cruciate ligament reconstruction

BACKGROUND

Tunnel widening after anterior cruciate ligament (ACL) reconstruction (ACLR) is commonly reported without a clear understanding of the mechanism. This study aimed to quantify the spatiotemporal change of the newly formed bone mass, bone tunnel diameter, and area along both bone tunnels using micro-computed tomography (microCT) and correlated the result with histology.

METHODS

ACLR was performed in 24 rabbits. At baseline and weeks 2, 6, and 12, the juxta-articular, middle, and exit segments of both tunnels were harvested for microCT and histological evaluation.

RESULTS

microCT and histology revealed significant bone tunnel and graft-bone tunnel healing, respectively, only at week 6 after reconstruction. Despite this, the mean tunnel diameter and area remained relatively unchanged with time. The newly formed bone mass [new bone volume/total bone volume (BV/TV) ratio] and its bone mineral density (BMD) were both higher, whereas the mean tunnel diameter and area were significantly smaller at the femoral tunnel compared to those at the tibial tunnel at weeks 6 and 12 and at week 12, respectively. These were consistent with histological findings, which showed inferior graft remodeling and integration at the tibial tunnel at weeks 6 and 12. The BV/TV increased, whereas the mean tunnel diameter and area decreased toward the exit segment of both tunnels. However, whereas better histological healing occurred at the femoral exit segment, poorer graft remodeling and Sharpey's fiber formation occurred at the tibial exit segment.

CONCLUSIONS

Poor healing was observed during the initial 6 weeks, particularly that of the tibia, after ACLR. Bone resorption was rapid during healing, resulting in unchanged tunnel diameter and area with time.

CALAXO osteoconductive interference screw: the value of postmarket surveillance

The CALAXO osteoconductive interference screw was recalled in August 2007 due to reports of increased numbers of postoperative complications associated with screw swelling and prominence leading to the need for surgical debridement. This study reviews complications associated with CALAXO screw use in a consecutive cohort of patients undergoing anterior cruciate ligament reconstruction surgery by the senior author at the authors' institution. Over a 12-month period, 226 CALAXO interference screws, either of 20 mm length or 25 mm length, were implanted in 112 patients, and postoperative complications were noted. The 25-mm tibial screw was over 5 times (RR 5.2, 95% CI 1.8 to 15.3) more likely to be prominent than the 20-mm screw (p value=.002). Four surgical debridements were required in the 25-mm tibial screw group; none were required in the 20-mm group. The authors hypothesize that the inability to bury the longer screw length into the bone tunnel is associated with postoperative complications associated with the CALAXO screw.

Predictive formula for the length of tibial tunnel in anterior crucitate ligament reconstruction

BACKGROUND

The anterior cruciate ligament (ACL) reconstruction using bone-patellar tendon bone graft is a common procedure in orthopedics. One challenging problem found is a graft-tunnel mismatch. Previous studies have reported the mathematic formula to predict the tibial angle length and angle to avoid graft-tunnel mismatch but these formulas have shown limited predictability.

OBJECTIVE

To propose a predictive formula for the length of tibial tunnel and to examine its predictability.

MATERIAL AND METHOD

Thirty six patients (26 males, 14 females) with ACL injury were included in this study. The preoperativemedial proximal tibial angle was measured. Intraoperatively, the tibial tunnel length and tibial entry point were measured. The postoperative coronal and saggital angle of tibial tunnel were measured from knee radiograph. The data were analysed by using trigonometry correlation and formulate the predictive formula of tibial tunnel length.

RESULTS

We found that tibial tunnel length (T) has trigonometric correlation between the location of tibial tunnel entry point (w), coronal angle of tibial tunnel (b), saggital angle of tibial tunnel (a) and the medial proximal tibial slope (c) by using this formula T = Wcos(c)tan(b)/sin(a)

CONCLUSION

This proposed predictive formula can well predict the length of the tibial tunnel at preoperative period to avoid graft-tunnel mismatch.

Anterior cruciate ligament graft tear. Primary and secondary magnetic resonance signs

Magnetic resonance (MR) imaging is a useful tool for assessing the anterior cruciate ligament (ACL) graft when its integrity is in question, with some limitations. It can differentiate between a graft that is partially or completely torn. Several primary (direct) and secondary (indirect) signs have been described. Graft continuity in the coronal plane and normal graft thickness in the coronal or sagittal plane are the most valuable primary signs in excluding full thickness tear. Of the secondary signs, the anterior tibial translation and the uncovered lateral meniscus sign are the most useful in differentiating a torn from an intact graft. Some of the primary and secondary signs of a native ACL tear are yet to be assessed for accuracy in detecting grafts tear, but they are a helpful guide especially when combined. These include the deep lateral femoral sulcus, the posterior cruciate ligament (PCL) angle, and the PCL curvature values.

Tunnel enlargement after anterior cruciate ligament reconstruction in patients with post-operative septic arthritis

Tunnel enlargement is a frequent issue after ACL reconstruction and the "synovial bathing effect" is thought to be among the biological factors contributing to this phenomenon. Since the amount and the pressure of the synovial fluid inside the knee joint are higher and the length of its presence is longer in patients with post-operative septic arthritis after ACL reconstruction, we reviewed the tunnel enlargement in these cases in order to better evaluate this phenomenon in such a hostile environment. The null hypothesis of this study was that the highly represented phenomenon of the "synovial bathing effect" that occurs in an infected ACL reconstruction would not affect the amount of post-operative tunnel widening. A case-control study was done. At a mean follow up of 10 months (range 9-11 months) eight patients with septic arthritis following ACL reconstruction (group A) were radiologically reviewed using a CT scan and the diameters of femoral and tibial tunnels were measured. The results were compared with a control group (B) of uncomplicated ACL reconstruction cases operated by the same surgeon using the same technique. Although patients of Group A experienced a bigger amount of tunnel enlargement than patients of group B both on femoral (9.53 +/- 1.07 vs. 9.35 +/- 1.52 mm) and tibial side (10.07 +/- 1.3 vs. 9.92 +/- 0.74 mm), no clinical or statistically significant differences were detected between the groups (P > 0.05). No significant tunnel enlargement could be detected in patients of group A when compared with patients of group B. This seems to minimize the role of biological factors contributing to tunnel widening.

Treatment of persistent extraarticular infection using a temporary cement spacer on the tibia after ACL reconstruction

Postoperative infection after anterior cruciate ligament (ACL) reconstruction is an uncommon but serious complication. Although several treatments for intraarticular infection have been reported, no report has been recorded on the treatment of persistent extraarticular infections. The authors experienced reconstructed graft removal due to a refractory extraarticular infection on tibia. Early ACL reimplantation was performed using a temporary cement spacer containing antibiotics and a irradiated bone patellar tendon bone allograft.

Septic arthritis with Staphylococcus lugdunensis following arthroscopic ACL revision with BPTB allograft

Septic arthritis following anterior cruciate ligament reconstruction is an uncommon but a serious complication resulting in six times greater hospital costs than that of uncomplicated ACL surgery and an inferior postoperative activity level. Promptly initiating a specific antibiotic therapy is the most critical treatment, followed by open or arthroscopic joint decompression, debridement and lavage. Staphylococcus lugdunensis is a coagulase-negative staphylococcus predominantly infecting the skin and soft tissue. The few reported cases of bone and joint infections by S. lugdunensis indicate that the clinical manifestations were severe, the diagnosis elusive, and the treatment difficult. If the microbiology laboratory does not use the tube coagulase (long) test to confirm the slide coagulase test result, the organism might be misidentified as Staphylococcus aureus. S. lugdunensis is more virulent than other coagulase-negative staphylococcus; in many clinical situations it behaves like S. aureus, further increasing the confusion and worsening the expected outcome. S. lugdunensis is known to cause infective endocarditis with a worse outcome, septicemia, deep tissue infection, vascular and joint prosthesis infection, osteomyelitis, discitis, breast abscess, urine tract infections, toxic shock and osteitis pubis. We present the first case report in the literature of septic arthritis with S. lugdunensis following arthroscopic ACL revision with bone-patellar-tendon-bone allograft.

Devastating femoral osteomyelitis after anterior cruciate ligament reconstruction

Osteomyelitis following arthroscopic assisted anterior cruciate ligament (ACL) reconstruction has not been reported in literature. We describe an aggressive progression of septic arthritis and osteomyelitis leading to the complete destruction of the condylar region in a young non-immunosuppressed patient after reconstruction of the ACL. In addition we discuss the steps in diagnostics and our salvage procedures.

[Posterior femoral cortex perforation unrecognised during arthroscopic LCA reconstructive surgery]

One of the most important technical demands in ACL surgery is good fixation of the graft. Integrity of the posterior femoral cortex is necessary for Interference screws fixation. The femoral tunnel, placed as posterior as possible, is also mandatory for good graft position and potentially leads to violation of the cortex. The divergence between screw and tunnel could result in perforation of the posterior wall. Without intraoperative x-ray it is difficult to be sure that position of the screw is correct, even with good graft tension. Still, the problem exists with absorbable screws. The aim of the study is to show results of 6 patients with this complication treated without revision of the femoral fixation with mean follow up of 1.5 year. Potential pitfall in ACL reconstruction is posterior cortex breakout and loss of fixation. If it is recognized during surgery changing the type of fixation can solve the problem, but if not, in the early phase of rehabilitation and weight bear, graft failure is feasible. The tibia tunnel angle and length, the footprint of femoral tunnel reamer and hyper flexion of the knee during screw insertion are methods for preventing the breakout of the posterior wall and screw-tunnel divergence. Modification of the early postoperative treatment and less aggressive rehabilitation protocol reduced the need for revision surgery. Even with best surgical technique, skill and experience this complication is possible to occur.

Delayed surgical intervention for a severe fixed flexion deformity of the knee following anterior cruciate ligament reconstruction

We report a case of severe fixed flexion deformity of the knee, following anterior cruciate ligament (ACL) reconstruction, due to protrusion of the bone block and fixation screw into the knee joint above the tibial tunnel. This was treated successfully after a latent period of 6 years with surgical intervention. This case highlights the importance of critical review of radiographic imaging when faced with a fixed flexion deformity of the knee after ACL surgery and the ability to achieve a good outcome from simple surgical intervention even after a long latent period.

Hamstring tendon autograft better than bone patellar-tendon bone autograft in ACL reconstruction: a cumulative meta-analysis and clinically relevant sensitivity analysis applied to a previously published analysis

BACKGROUND

Current debate on treatment options for anterior cruciate ligament (ACL) reconstruction complicate the choice between hamstring and bone-patellar tendon-bone autografts. We hypothesized a priori that cumulative meta-analysis (a form of sensitivity analysis) might show that the evidence for reduction of morbidity by hamstring grafts could have been reached at an earlier time. Furthermore, we hypothesized a priori that modern state-of-the-art hamstring graft fixation technique would give similar results regarding stability as bone-patellar tendon-bone autografts.

METHODS

We performed a cumulative meta-analysis and sensitivity analysis based on femoral graft fixation techniques to compare hamstring autograft and bone-patellar tendon-bone autografts in ACL reconstruction derived from a previously published meta-analysis.

RESULTS

Cumulatively, that hamstring autograft reduces anterior knee pain had already reached statistical significance in 2001 (relative risk 0.49 (95%CI: 0.32-0.76; p = 0.001, I2 = 0%)). The modern endobutton hamstring graft fixation technique (2 studies) yielded similar stability in the Lachman test as bone-patellar tendon-bone grafts, with a relative risk of 1.1 (95%CI: 0.82-1.5; p = 0.6, I2 = 0%). Exclusion of the endobutton group explains the increased laxity in the hamstring graft group.

INTERPRETATION

Cumulative meta-analysis strengthens the evidence for reduced morbidity using hamstring tendon autograft for anterior cruciate ligament reconstruction. Sensitivity analysis focusing on state-of-the-art hamstring graft fixation techniques further weakens the evidence that bone-patellar tendon-bone autografts provide better stability.

Removal of a femoral interference screw that migrated posteriorly, using a posterior trans-septal portal: a case report

Few cases have been reported in which the femoral interference screw has migrated into the posterior compartment after an ACL reconstruction. It usually requires removal, because it leads usually to mechanical symptom. However, the arthroscopic removal of a screw is a technically demanding procedure, especially in the case of the femoral interference screw that has migrated into the femoral notch (posterior compartment), an intact integrated ACL graft or one that is encapsulated around the screw. We present a case in which a displaced femoral interference screw migrated within the posterior compartment 11 years postoperatively, after the graft had been incorporated at the femoral site. Although it is often technically challenging, through the use of a posterior trans-septal portal, we can successfully remove a displaced femoral interference screw even in the most difficult locations in the posterior compartment.

Randomized prospective study of ACL reconstruction with interference screw fixation in patellar tendon autografts versus femoral metal plate suspension and tibial post fixation in hamstring tendon autografts: 5-year clinical and radiological follow-up results

Patellar tendon graft has been the most frequently used material in anterior cruciate ligament (ACL) reconstruction, but the hamstring tendons have been increasingly used as well; however, which graft is to be preferred is not adequately supported by existing clinical studies. In this prospective randomized clinical trial, the study hypothesis was that the hamstring tendons are equally good graft material as the patellar tendon in ACL reconstruction. Ninety-nine patients with laxity due to a torn ACL underwent arthroscopically assisted reconstruction with graft randomization according to their birth year to either patellar tendon with metal interference screw fixation or double looped semitendinosus and gracilis tendons with fixation similar to the Endobutton technique using a titanium metal plate suspension proximally and screw-washer postdistally. Excluding preoperative Lysholm knee score, there were no significant differences between the two groups in the preoperative and operative data. A standard rehabilitation regimen was used for all the patients, including immediate postoperative mobilization without a knee brace, protected weight bearing for 2 weeks, and return to full activity at 6-12 months postoperatively. Forty patients in the patellar tendon group and 39 patients in the hamstring tendon group were available for clinical evaluation at median 5 years after surgery (ranges 3 years 11 months-6 years 7 months). The results revealed no statistically significant differences with respect to clinical and instrumented laxity testing, isokinetic muscle torque measurements, International Knee Documentation Committee ratings, Lysholm (knee score), Tegner (activity level) and Kujala patellofemoral knee scores. There was an enlargement of the drill tunnels, statistically more in the hamstring tendon group, but no increase from 2 to 5 years in either group. Narrowing of the joint spaces (IKDC measurement method) from 2 to 5 years postoperatively was seen in both the groups, however, without difference between the two groups.

Loose intra-articular body following anterior cruciate ligament reconstruction

We report a case of intra-articular fracture of a bioabsorbable fixation device from the femoral tunnel in an anterior cruciate ligament reconstruction using a bone-tendon-bone graft. Thirteen months after successful reconstruction surgery, the patient experienced episodes of locking and medial joint pain. There was no history of trauma and no symptoms of instability or swelling. On revision arthroscopy, a fractured tip of a bioabsorbable RIGIDfix cross pin (Mitek, Westwood, MA) was identified in the medial compartment of the knee. There was a broad area of chondral erosion affecting the medial femoral condyle and a small defect to the medial tibial plateau where the loose body had been lodged. The bone-tendon-bone graft was intact without disruption. After arthroscopy, the patient was symptom free for 3 weeks but then developed further symptoms of locking. Magnetic resonance imaging showed another loose body within the knee. A repeat arthroscopy was performed 6 weeks after the earlier procedure and another piece of the polylactic acid RIGIDfix cross pin was removed, this time from the lateral gutter. This case raises concern about the potential for breakage and resultant loose body formation that may occur after bioabsorbable cross-pin fixation and, particularly, the associated chondral damage that can occur if early intervention is not conducted.