Outcomes of ACL Reconstruction Utilizing Supercritical CO2-Sterilized Allografts.

Background: Allograft tendons are perceived to have a high ACL graft failure rate in primary anterior cruciate ligament (ACL) reconstruction (ACLR). Historical series may be biased by graft processing methods that degrade the biomechanical properties of donor tendons such as irradiation. Supercritical carbon dioxide (SCCO2) is a validated method of terminally sterilizing biomaterials at physiological temperatures without irradiation, but in vivo use of SCCO2-processed tendon allografts for primary ACLR has not been reported to date. Hypothesis: ACLR with SCCO2 allografts would result in acceptable failure rates, subjective knee scores, and clinical evaluation at 2 years postoperatively. Study Design: Case series; Level of evidence, 4. Methods: Patients underwent primary ACLR with terminally sterilized SCCO2-processed human gracilis, peroneus longus, semitendinosus, tibialis anterior, and tibialis posterior tendon allografts. Patient demographics were collected, along with tendon donor age and sex. At 1 year postoperatively, subjective International Knee Documentation Committee (IKDC) and ACL-Return to Sport After Injury (ACL-RSI) scores were collected, as well as clinical evaluation. At 2 years postoperatively, the IKDC and ACL-RSI scores were repeated, and return to sports and further knee injuries were recorded. Results: A total of 144 patients with a medianage of 26 (IQR 14) years formed the study group. Patients were predominately male (58%). The loss to follow-up rate was 8% (n = 12). The mean age of allograft tendon donors was 37 (range 17-58) years, and the majority were male (83%). The mean allograft diameter was 8.9 ± 1.0 mm. At 2 years, ACL graft failureoccurred in 5% (n = 7). All graft failureswere in patients aged ≤25 years (P = .007). Neither donor age (≤40 or >40 years) nor donor sex was associated with graft failure (P > .05). The median IKDC subjective score was 95 and ACL-RSI score was 75. There were no revisions for sepsis within the first 2 years postoperatively. Conclusion: SCCO2 processing of allograft tendons demonstrated satisfactory clinical and patient-reported outcomes at 24 months postoperatively in a consecutive series of patients with primary ACLR, with similar ACL graft failure rates and subjective knee scores compared with those reported in published series of hamstring tendon autograft and fresh frozen nonirradiated allograft.

20-Year Outcomes of High Tibial Osteotomy: Determinants of Survival and Functional Outcome.

BACKGROUND: High tibial osteotomy (HTO) is a successful joint-preserving procedure for the treatment of medial compartment osteoarthritis. Long-term survivorship of HTO ranges from 40% to 85%. There are consistent factors that predict failure. PURPOSE: To determine the 20-year survival of HTO and identify predictors of failure. STUDY DESIGN: Case series; Level of evidence, 4. METHODS: A total of 100 consecutive patients with medial bone-on-bone arthritis were prospectively studied to provide long-term patient-reported outcome measures after lateral closing-wedge HTO and determine the time to failure. Failure was defined as conversion to arthroplasty (total knee arthroplasty or unicompartmental knee arthroplasty) or revision HTO. RESULTS: At 20 years, HTO survival was determined in 95 patients, and 5 were lost to follow-up. The overall survivorship of HTO at 20 years was 44%. The significant factors that were associated with better survivorship were age <55 years, body mass index <30, and Western Ontario and McMaster Universities Osteoarthritis Index pain score >45. These factors were used to define the favorable candidates. In the favorable candidates, survivorship was 100% at 5 years, after which there was a gradual decline to 62% survival at 20 years. Of those with HTO survival, 32 of 33 (97%) reported satisfaction with surgery, with a mean Knee injury and Osteoarthritis Outcome Score Pain score of 91 and Activities of Daily Living score of 97. CONCLUSION: HTO is a successful surgical option to treat medial compartment osteoarthritis and prevent the need for arthroplasty in young patients. The most suitable candidates for HTO are aged <55 years, are not obese, and have not progressed to severe symptomatic disability.

A 10-year comparison of anterior cruciate ligament reconstructions with hamstring tendon and patellar tendon autograft: a controlled, prospective trial.

BACKGROUND: There are no controlled, prospective studies comparing the 10-year outcomes of anterior cruciate ligament (ACL) reconstruction using patellar tendon (PT) and 4-strand hamstring tendon (HT) autografts. HYPOTHESIS: Comparable results are possible with HT and PT autografts. STUDY DESIGN: Cohort study; Level of evidence, 2. METHODS: One hundred eighty ACL-deficient knees that met inclusion criteria underwent ACL reconstruction (90 HT autograft, 90 PT autograft) by one surgeon and were treated with an accelerated rehabilitation program. All knees were observed in a prospective fashion with subjective, objective, and radiographic evaluation at 2, 5, 7, and 10-year intervals. RESULTS: At 10 years, there were no differences in graft rupture rates (7/90 PT vs. 12/90 HT, P = .24). There were 20 contralateral ACL ruptures in the PT group, compared with 9 in the HT group (P = .02). In all patients, graft rupture was associated with instrumented laxity >2 mm at 2 years (P = .001). Normal or near-normal function of the knee was reported in 97% of patients in both groups. In the PT group, harvest-site symptoms (P = .001) and kneeling pain (P = .01) were more common than in the HT group. More patients reported pain with strenuous activities in PT knees than in HT knees (P = .05). Radiographic osteoarthritis was more common in PT knees than the HT-reconstructed knees (P = .04). The difference, however, was composed of patients with mild osteoarthritis. Other predictors of radiographic osteoarthritis were <90% single-legged hop test at 1 year and the need for further knee surgery. An "ideal" outcome, defined as an overall International Knee Documentation Committee grade of A or B and a radiographic grade of A at 10 years after ACL reconstruction, was associated with <3 mm of instrumented laxity at 2 years, the absence of additional surgery in the knee, and HT grafts. CONCLUSIONS: It is possible to obtain excellent results with both HT and PT autografts. We recommend HT reconstructions to our patients because of decreased harvest-site symptoms and radiographic osteoarthritis.

Revision anterior cruciate ligament reconstruction with hamstring tendon autograft: 5- to 9-year follow-up.

BACKGROUND: The results of revision anterior cruciate ligament reconstruction are limited in the current literature, and no studies have previously documented the outcome of revision anterior cruciate ligament reconstruction using solely hamstring tendon grafts. HYPOTHESIS: Revision anterior cruciate ligament reconstruction with 4-strand hamstring tendon graft affords acceptable results and is comparable to reported outcomes with the bone-patellar tendon-bone graft. STUDY DESIGN: Case series; Level of evidence, 4. METHODS: Fifty-seven consecutive revision anterior cruciate ligament reconstructions with the hamstring tendon graft and interference screw fixation were assessed a mean time of 89 months (range, 60-109 months) after surgery. Assessment included the International Knee Documentation Committee knee ligament evaluation, instrumented laxity testing, and radiologic examination. RESULTS: Of the 50 knees reviewed, 5 (10%) had objective failure of the revision anterior cruciate ligament reconstruction. Of the 45 patients with functional grafts, knee function was normal or nearly normal in 33 patients (73%). An overall grade of normal or nearly normal was found in 56% of patients. The mean side-to-side difference on manual maximum testing was 2.5 mm (range, -1 to 4 mm). Degenerative changes on radiographs were identified in 23% of patients at the time of surgery, increasing to 56% of patients at review. The status of the articular cartilage at the time of revision surgery was the most significant contributor to successful outcome. CONCLUSION: Revision anterior cruciate ligament reconstruction with hamstring tendon graft and interference screw fixation affords acceptable results at a minimum of 5 years' follow-up. Good objective results can be obtained, but subjectively, the results appear inferior to those of primary anterior cruciate ligament reconstruction in the literature, which may be related to the high incidence of articular surface damage in this patient population. We recommend that, when available, hamstring tendon autografts should be considered for revision anterior cruciate ligament reconstruction.

Long-term outcome of endoscopic anterior cruciate ligament reconstruction with patellar tendon autograft: minimum 13-year review.

BACKGROUND: Short-term results of anterior cruciate ligament reconstruction are well reported; however, there are no studies evaluating endoscopic reconstruction of the anterior cruciate ligament with a minimum 10-year follow-up. HYPOTHESIS: Anterior cruciate ligament reconstruction with patellar tendon graft affords good subjective results and clinical laxity assessments but may be associated with development of osteoarthritis over the long term. STUDY DESIGN: Case series; Level of evidence, 4. METHODS: Endoscopic anterior cruciate ligament reconstruction was performed in 67 consecutive patients without significant articular surface damage. Patients were assessed at 5, 7, and 13 years after surgery with the International Knee Documentation Committee Knee Ligament Evaluation Form, Lysholm knee score, hop tests, kneeling pain, and radiographs. RESULTS: At 13-year review, self-reported assessments remained excellent; 96% of patients reported normal or nearly normal knee function. Grade 0 or 1 results were seen in more than 92% of patients on laxity testing. Patients who had undergone meniscectomy at the time of reconstruction had increased laxity between 7 and 13 years on instrumented testing (P = .03) and 6 times greater odds of anterior cruciate ligament graft rupture than if they had not undergone meniscectomy (95% confidence interval, 1-37). Degenerative changes on radiographs were found in 79% of patients at 13 years and were associated with meniscectomy (P = .006), loss of extension (P = .05), and greater laxity on Lachman test (P = .04). CONCLUSIONS: Endoscopic anterior cruciate ligament reconstruction with patellar tendon autograft affords and maintains good self-reported assessments and clinical ligament evaluation up to 13 years. Radiographic degenerative changes were seen in three quarters of patients. Almost half developed loss of extension, suggesting onset of early osteoarthritis. Patients who had undergone meniscectomy at the time of reconstruction had increased clinical ligament laxity over time and greater odds of graft rupture, possibly reflecting the effect of prolonged increased strain on the graft. Continued follow-up is required to resolve concerns regarding integrity of the patellar tendon graft beyond 13 years, particularly in the absence of meniscal tissue.

Gender differences in outcome after anterior cruciate ligament reconstruction with hamstring tendon autograft.

BACKGROUND: It is now well documented that women are more likely to suffer anterior cruciate ligament injuries than are men. A few studies have examined gender differences in the outcome of anterior cruciate ligament reconstruction with patellar tendon graft and hamstring tendon with EndoButton fixation, but no well-controlled studies have specifically compared men and women after anterior cruciate ligament reconstruction with hamstring tendon graft and interference screw fixation. HYPOTHESIS: There is no difference in outcome between men and women after anterior cruciate ligament reconstruction with hamstring tendon autograft and interference screw fixation. STUDY DESIGN: Cohort study; Level of evidence, 3. METHODS: There were 100 men and 100 women who underwent isolated anterior cruciate ligament reconstruction by a single surgeon. Patients were assessed preoperatively and at 1, 2, and 7 years after surgery. Variables were compared between female and male patients. RESULTS: Laxity on physical evaluation was greater in women than in men on Lachman (P = .04), pivot-shift (P = .05), and mean manual maximum testing (P = .05) at 7 years. However, the magnitude of this difference was small. No patient had a greater than grade 1 Lachman or pivot-shift test result, and the mean difference between men and women was 0.6 mm on instrumented testing. Anterior cruciate ligament graft rupture occurred in 11 men and 10 women. There was no difference between male and female patients for self-reported knee function or symptoms of instability or radiologic examination. CONCLUSION: Anterior cruciate ligament reconstruction using hamstring tendon autograft affords excellent self-reported and objective results in both men and women after 7 years. Although significantly greater laxity on physical examination was present in female patients than in male patients, the magnitude of this difference was small and had no effect on activity level, graft failure, or subjective or functional assessment.

Incidence and risk factors for graft rupture and contralateral rupture after anterior cruciate ligament reconstruction.

PURPOSE: The aim of this study was to determine the rates of contralateral anterior cruciate ligament (ACL) rupture and of ACL graft rupture after ACL reconstruction using either patellar tendon or hamstring tendon autograft, and to identify any patient characteristics that may increase this risk. TYPE OF STUDY: Case series. METHODS: Over a 2-year period, 760 endoscopic ACL reconstructions were performed in 743 patients. Bone-patellar tendon-bone autograft was used in 316 patients and 4-strand hamstring tendon in 427 patients. Those patients with a previous contralateral ACL rupture or those who underwent a simultaneous bilateral ACL reconstruction were excluded, leaving 675 knees (675 patients) for review. Persons not involved in the index operation or the care of the patient conducted follow-up assessment by telephone interview conducted 5 years after surgery. Patients were questioned about the incidence of ACL graft rupture, contralateral ACL rupture, symptoms of instability or significant injury, family history of ACL injury, and activity level according to the International Knee Documentation Committee scale. From our prospective database we obtained further information on graft source, meniscal or articular surface injury, and gender. Binary logistic regression was used to measure the relative association between the measured variables and the risk of graft rupture and contralateral ACL rupture. RESULTS: Five years after primary ACL reconstruction, 612 of the 675 patients (90.7%) were assessed. ACL graft rupture occurred in 39 patients (6%) and contralateral ACL rupture occurred in 35 patients (6%). Three patients suffered both a graft rupture and a contralateral ACL injury. The odds of ACL graft rupture were increased 3-fold by a contact mechanism of initial injury. Return to level 1 or 2 sports increased the risk of contralateral ACL injury by a factor of 10. The risk of sustaining an ACL graft rupture was greatest in the first 12 months after reconstruction. No other studied variable increased the risk of repeat ACL injury. CONCLUSIONS: After reconstruction, repeat ACL injury occurred in 12% of patients over 5 years. Twelve months after reconstruction, the ACL graft is at no greater risk than the contralateral ACL, suggesting that adequate graft and muscular function for most activities is achieved by this time. Risk factors for repeat ACL injury identified included a return to competitive side-stepping, pivoting, or jumping sports, and the contact mechanism of the index injury. Female patients were at no greater risk of repeat ACL injury than male patients and graft choice did not affect the rate of repeat ACL injury. LEVEL OF EVIDENCE: Level IV, case series.

A 7-year follow-up of patellar tendon and hamstring tendon grafts for arthroscopic anterior cruciate ligament reconstruction: differences and similarities.

BACKGROUND: For arthroscopic anterior cruciate ligament reconstruction, the most commonly used graft constructs are either the hamstring tendon or patellar tendon. Well-controlled, long-term studies are needed to determine the differences between the 2 materials. HYPOTHESIS: There is a difference between hamstring and patellar tendon grafts in the clinical results of anterior cruciate ligament reconstructions at 7 years. STUDY DESIGN: Cohort study; Level of evidence, 2. METHODS: Two groups of 90 patients each, consecutively treated with hamstring or patellar tendon grafts, were followed and assessed at 1, 2, 5, and 7 years after surgery. RESULTS: At the 7-year review, abnormal radiographic findings were seen in 45% (24/53) of the patellar tendon group and in 14% (7/51) of the hamstring tendon group (P = .002). Although there was no significant difference between the groups in extension deficit (P = .22), the percentage of patients with an extension deficit increased significantly in the patellar tendon group from 8% at 1 year to 25% at 7 years (P = .02). No significant change was seen in the hamstring tendon group over time (P = .20). There was no significant difference in laxity between the groups on Lachman (P = .44), pivot-shift (P = .39), or instrumented (P = .44) testing. Graft rupture occurred in 4 patients from the patellar tendon group and in 9 patients from the hamstring tendon group (P = .15). Both autografts gave excellent subjective results, as evidenced by the International Knee Documentation Committee evaluation and Lysholm knee scores at 7 years. CONCLUSIONS: Both hamstring and patellar tendon grafts provided good subjective outcomes and objective stability at 7 years. No significant differences in the rate of graft rupture or contralateral anterior cruciate ligament rupture were identified. Patients with patellar tendon grafts had a greater prevalence of osteoarthritis at 7 years after surgery; therefore, the authors preferred hamstring tendons as the primary graft choice in anterior cruciate ligament reconstructions.

The influence of supplementary tibial fixation on laxity measurements after anterior cruciate ligament reconstruction with hamstring tendons in female patients.

BACKGROUND: Female patients undergoing arthroscopic anterior cruciate ligament reconstruction with a hamstring tendon graft developed increased postoperative laxity compared to male and female patients who had reconstruction using a patellar tendon graft. This difference may be due to graft slippage in less dense female tibial bone. HYPOTHESIS: Reinforcement of tibial fixation of the hamstring tendon graft in women by supplementary methods may reduce laxity. STUDY DESIGN: Randomized controlled clinical trial; Level of evidence, 2. METHODS: Fifty-six female patients divided into 2 groups (standard tibial fixation with 7 x 25-mm metal interference screw versus metal interference screw with supplementary staple fixation) were followed for 2 years. RESULTS: After 2 years, the mean side-to-side difference using KT-1000 arthrometer manual maximum measurements was 1.8 mm (standard group) and 1.1 mm (staple group) (P=.05). The percentage of patients with a side-to-side difference of <3 mm did not differ significantly between the 2 groups (P=.66): 88.8% of the standard group versus 90.5% of the staple group. A grade 0 Lachman test result was present in 63% of the standard group and 86% of the staple group (P=.04). Kneeling pain was experienced by 7% of the standard group and 29% of the staple group (P=.05). CONCLUSIONS: Supplementary tibial fixation in female patients undergoing anterior cruciate ligament reconstruction with hamstring tendon graft in addition to a single-size screw significantly improves laxity measurements and clinical stability assessment 2 years after surgery. However, this improvement is at the cost of increased kneeling pain.

Endoscopic single-bundle posterior cruciate ligament reconstruction: results at minimum 2-year follow-up.

PURPOSE: The goal of this study was to evaluate the clinical outcome of single-bundle posterior cruciate ligament (PCL) reconstruction with retention of the PCL remnant and hamstring tendon autograft with interference screw fixation in patients with isolated PCL laxity. TYPE OF STUDY: Prospective case series with minimum 2-year follow-up evaluation. METHODS: Thirty-one patients for whom conservative management had failed underwent surgery using a 4-strand hamstring tendon autograft with interference screw fixation. The median time from injury to reconstructive surgery was 9 months (range, 4 to 120 months). At a minimum of 2 years after surgery, patients were assessed with the International Knee Documentation Committee (IKDC) Knee Ligament evaluation, Lysholm knee score, and KT-1000 instrumented testing. RESULTS: Before surgery, the median Lysholm knee score was 64 (95% confidence interval, 51 to 67). No patient rated knee function as normal, and all patients showed at least grade 2 posterior drawer laxity. At review, the median Lysholm knee score was 94 (95% confidence interval, 83 to 94), 56% rated the knee as normal and only one patient was found to exhibit grade 2 laxity on posterior drawer testing. Before injury, 94% of patients participated in moderate or strenuous activity. This figure fell to 26% after injury and had increased to 63% at review. CONCLUSIONS: Endoscopic reconstruction of PCL laxity using single-bundle 4-strand hamstring tendon autograft, without removal of the PCL stump, provides a significant reduction in knee symptoms and allows 63% of patients to return to moderate or strenuous activity. This is an effective procedure for symptomatic patients who have isolated PCL laxity and for whom conservative management has failed.

A five-year comparison of patellar tendon versus four-strand hamstring tendon autograft for arthroscopic reconstruction of the anterior cruciate ligament.

BACKGROUND: The choice of graft material for anterior cruciate ligament reconstruction is believed to play a major role in outcome, but most comparisons of graft choice have not been well controlled. HYPOTHESIS: The choice of graft material (patellar tendon or hamstring tendon) does affect clinical outcome after anterior cruciate ligament reconstruction. STUDY DESIGN: Prospective, nonrandomized clinical trial. METHODS: Two groups of 90 patients each were followed for a minimum of 5 years. RESULTS: International Knee Documentation Committee assessment revealed that more than 85% of each group had an overall score of A or B at all follow-up intervals. The median Lysholm knee score was greater than 90 for both groups at 2 and 5 years. Instrumented testing revealed no significant difference between the two groups beyond 3 years. Thirty-one percent of the patellar tendon group (25) had a fixed flexion deformity and 19% of the hamstring tendon group (14) had fixed flexion deformity at 5 years. Radiologic assessment revealed early osteoarthritic changes in 4% of the hamstring tendon group (2) and in 18% of the patellar tendon group (11) at 5 years. CONCLUSIONS: Arthroscopic reconstruction with either graft results in a similar surgical outcome, reliably restoring knee stability over a 5-year period; however, patients with patellar tendon grafts are at greater risk of developing early signs of osteoarthritis.

Concomitant partial meniscectomy worsens outcome after arthroscopic anterior cruciate ligament reconstruction.

In this multi-center study involving 412 patients, we assessed the influence of concomitant partial meniscal resection on the medium-term clinical results after anterior cruciate ligament reconstruction. We performed a resection of minimum one-third of the medial or lateral menisci in 137 patients (group M) and found intact menisci in 275 patients (group NM). Those who had undergone previous meniscal surgery, subsequent meniscal surgery or a re-rupture of the anterior cruciate ligament graft during the follow-up were not included. After a median of 3 (2-6) years, the patients were reexamined by independent observers. Group M patients had more pain, swelling and laxity than those in group NM; they also had a worse classification according to the IKDC system, lower Lysholm scores and a greater proportion of patients with loss of motion.