Bone-block iliotibial-band transfer for anterior cruciate insufficiency

Patellofemoral problems after anterior cruciate ligament reconstruction

Between 1982 and 1986, 126 patients who had undergone ACL reconstruction were followed in a prospective manner. One year follow-up statistics were reviewed for the presence of 13 different complications. The most prevalent complications were quadriceps weakness, flexion contracture, and patellofemoral pain. Quadriceps weakness (strength less than 80% of the normal side) was present in 65% of patients and correlated positively with flexion contracture, patellar irritabibilty, and ACL reconstructions using patellar tendon grafts. Flexion contracture of 5 degrees or more was present in 24% of patients and correlated positively with increased age and patellar irritability. Patellofemoral pain was present in 19% of patients and correlated positively with flexion contracture.

CLINICAL RELEVANCE

The three most common complications of knee ligament surgery are shown to be strongly interrelated. It is likely that a causal relationship is present in which flexion contracture causes patellofemoral irritability, and that both of these factors, alone or in combination, result in quadriceps weakness. If this theory is correct, then it is crucial that postoperative rehabilitation programs place a major emphasis on the avoidance of flexion contracture.

Early experience with the GORE-TEX polytetrafluoroethylene anterior cruciate ligament prosthesis

A prospective study of 41 patients with acute and chronic ACL deficiency underwent reconstruction with the GORE-TEX polytetrafluoroethylene (PTFE) ACL prosthesis beginning in November 1983. Thirty-nine patients who were at least 2 years from their surgical procedure were available for follow-up evaluation, which included subjective questionnaire, clinical examination, and instrumented ligamentous laxity tests. Eight patients had an acute injury to the ACL and 31 patients had chronic ACL insufficiency for which reconstruction was performed. Thirty-four patients had satisfactory results, allowing full return to activity with no appreciable symptomatology. Of the remaining five patients, four had a complete rupture of the prosthesis. The average knee arthrometric measurement improved from a 5.4 mm left/right difference preoperatively to a 2.0 mm left/right difference at 2 year followup. Nine patients had postoperative complications of one or more atraumatic episodes of a sterile effusion. Six patients had recurrent effusions; in five, arthroscopy revealed partial tears of less than one-third of the prosthesis. Three patients who had recurrent effusions had PTFE particles in their synovial biopsies. One patient had an immediate postoperative infection and to data has had salvage of the prosthesis and currently has a stable knee with full return to activities. Based on the early results of this study, the GORE-TEX PTFE ACL prosthesis provided a satisfactory method of reconstruction for ACL deficient knees. Based on the evaluation used, 87% of the patients had satisfactory results. Problems associated with use of this prosthesis include partial or complete tears of the prosthesis and sterile effusions, possibly due to synovial irritation from the PTFE particles.(ABSTRACT TRUNCATED AT 250 WORDS)

Proprioception in the anterior cruciate deficient knee

Proprioception was quantified in a group of patients who had documented complete ACL tears. Threshold to detection of passive change in position of the knee was measured using a well-described test. Eleven patients with arthroscopically proven complete ACL tears and findings consistent with moderate to severe anterolateral rotatory instability were tested. Testing was done within the 30 degrees to 40 degrees range of knee flexion. Patients were blindfolded and the injured and uninjured knees were tested in random sequence so that the normal knee could serve as an internal control. Testing was also done in a blind manner, i.e., the examiner did not know which knee had been injured. An age-matched control group underwent identical testing. Potentially significant variables such as age, time from injury, and degree of rehabilitation as measured by thigh circumference and isokinetic testing of the knee were included in a multivariate analysis. Control subjects demonstrated virtually identical threshold values between their two knees, the mean variation being less than 2%. The test group, however, showed a significantly higher mean threshold value for the injured versus the noninjured knee (P less than 0.01), the mean variation being over 25%. Multivariate analysis demonstrated that changes recorded in the proprioception of the injured knee were attributable to the loss of the ACL rather than to other variables. Patients who have complete ACL tears and moderate to severe rotatory instability may also experience a decline in proprioceptive function of their knee.

Mechanical properties of primate vascularized vs. nonvascularized patellar tendon grafts; changes over time

Mechanical properties of patellar tendon autografts used to replace the anterior cruciate ligament (ACL) in the cynomolgus monkey were measured at four time periods up to 1 year. The ACL was replaced in each knee with the medial half of the patellar tendon: as a vascularized graft (VG) on one side and as a nonvascularized or free graft (FG) on the other. Postoperative care consisted of 4 weeks of cast immobilization at 30 degrees flexion followed by unrestricted activity in a large cage. Both grafts showed low stiffness and maximum force at 7 weeks (24% and 16% of ACL control values, respectively), increasing to 57% of control ACL stiffness and 39% of control maximum force by 1 year. Corresponding material properties, modulus and maximum stress, also increased over time, but at 1 year were only 34% and 26% of ACL values, respectively. The results indicate that retaining vascularity does not prevent significant reduction in graft properties that occur postoperatively, nor does it accelerate the return in strength and stiffness. Tissue stiffness, which returns earlier than maximum force and joint anteroposterior (AP) force displacement data, should be routinely reported in any healing study. Finally, in studies of this kind, the large variation in the results makes sampling only one or two animals from each time period unreliable.

Reconstruction of the anterior cruciate ligament. Long-term effects of different knee angles at primary immobilization and different modes of early training

The clinical results in 29 patients who had undergone ACL reconstruction with quadriceps-patellar tendon graft over-the-top were studied at an average of 28 months postoperatively. Postoperative immobilization was at either 30 degrees (N = 17) or 70 degrees (N = 12) of knee flexion for 6 weeks. All patients then followed a common preparatory training program for 8 weeks. In the 14th postoperative week the patients were put on either progressive resistance training (N = 12) or isokinetic training (N = 17) for 6 weeks, after which all had identical training. Independent of primary knee immobilization angle or training regimens, no differences could be demonstrated with respect to stability, range of motion, function, or isokinetic mechanical output. For all patients, Lysholm knee function score improved from 60.5 to 93.6 (P less than 0.001) and activity level from 3.9 to 6.3 (P less than 0.001). Isokinetic peak torque, contractional work, and mean power of the quadriceps at 30, 90, and 180 deg/sec were lower in the injured compared to the noninjured leg (78% to 90%; P less than 0.01) both preoperatively and at followup, and there were no significant differences between the preoperative and follow-up values. Clinical stability improved (P less than 0.001) in 19 of the 29 patients (66%) and in 11 of those 17 patients with early isokinetic training (65%). Performance tests were normal in 23 of 29 patients (79%), with minor abnormalities in the rest.

An in vitro study of anterior cruciate ligament graft placement and isometry

Isometric positioning of the ACL graft or prosthesis is an important consideration in successful reconstruction of the ACL-deficient knee. This study documented the relationship between graft placement and intraarticular graft length changes and graft tension changes during knee passive range of motion. Fifteen fresh cadaveric knees were mounted in stabilizing rigs. The ACL was identified and cut in each specimen. Intraarticular reconstruction was then performed using a 6 mm polypropylene braid (3M LAD, St. Paul, MN). The following graft placements were evaluated: 1) over-the-top, 2) modified over-the-top with a femoral bone trough, 3) femoral drill hole positions, and 4) tibial drill hole positions. The proximal end of the graft was fixed to the lateral aspect of the femur with a screw and spiked washer. The distal end of the graft was attached to a turnbuckle attached to a load cell on the anterior aspect of the tibia. The knee was then extended passively from 90 degrees to 0 degrees. Two experiments were performed. In Experiment A, the turnbuckle was adjusted to keep graft tension constant and the graft length changes were recorded. In Experiment B, the graft fixation sites were not altered and tension changes with range of motion were recorded. A change in the graft distance between attachment sites with knee range of motion can be monitored either by ligament length or by tension change. With the over-the-top technique, in Experiment A, the graft distance between attachment sites increased as the knee was extended (means = 4.9 mm); in Experiment B, large tension increases were recorded with knee extension.(ABSTRACT TRUNCATED AT 250 WORDS)

Biomechanics of fascia lata ligament replacements: early postoperative changes in the goat

Mechanical properties of fascia lata autografts used to replace the anterior cruciate ligament (ACL) in the goat were measured at 0, 2, 4, and 8 weeks after surgery. The ACL was replaced in the right knee of 50 animals divided equally into two groups according to graft fixation technique: (a) two smooth staples at each end, with the tissue pulled back toward the joint over the first staple and (b) reinforced fixation with a spiked bushing placed through the tissue and a 3-cm-long flat polypropylene braid sutured to each end of the graft. Eleven unoperated contralateral knees were tested as controls. All statistically significant effects of the reinforced versus staple fixation were observed at 0 weeks, with the reinforced group showing less anteroposterior (AP) translation of the joint and greater maximum force and stiffness of the femur-graft-tibia units. The reinforced group had increased AP translation and decreased strength and stiffness by 2 weeks after surgery. Increased AP translation resulted primarily from increases in the low-stiffness region of the force-displacement curve (primary AP translation) and to a lesser extent from increased translation in the high-stiffness region (secondary anterior translation). Failures at 0 weeks with the reinforced fixation occurred at the bushing or end of the reinforcing braid, while all but one of the later failures occurred in the tissue mid-substance. In the staple group, maximum force was greater at 8 weeks than at 0 weeks, as the failure locations changed from the fixation to the tissue mid-substance.(ABSTRACT TRUNCATED AT 250 WORDS)

Ligament length relationships in the moving knee

This article presents an investigation of potential ligament attachment sites for surgical reconstruction of the anterior and posterior cruciate ligaments as well as for the lateral extraarticular iliotibial band tenodesis. Our methodology was based on quantitative measurements of knee anatomy and motion in fresh cadavers, not on biomechanical modeling. Using computer search techniques, we located all the ligament insertion sites that were nearly isometric for motion of the intact knee.

Determination of graft tension before fixation in anterior cruciate ligament reconstruction

This study was performed to determine the tension needed to be applied on an anterior cruciate ligament graft before fixation to obtain normal anteroposterior translation following an anterior cruciate ligament reconstruction. Ten fresh-frozen cadaver knees underwent arthroscopy and were determined to have intact anterior and posterior cruciate ligaments and both menisci. A knee arthrometer (model KT 1000. MedMetric Corp., San Diego, CA, U.S.A.) was used to determine the anteroposterior translation with a 20 lb load. The anterior cruciate ligament was arthroscopically sectioned, and a repeat arthrometer measurement was made. Isometric points in the femur and tibia were determined using a tension isometer before drilling bony tunnels. The central third patellar tendon (bone-tendon-bone) complex, semitendinosus that was doubled on itself, and an iliotibial band approximately 3 cm wide were harvested. The grafts were separately passed through the knee, the femoral end was secured, and various tensions were applied to the tibial end before fixation. Repeat knee arthrometer measurements were performed after each new tension was applied. Arthrometer testing was continued until the postreconstruction 20 lb anterior drawer equalled the anterior cruciate ligament intact drawer. The patellar tendon returned the knee to its preoperative condition with a mean 3.6 lb of tension, the semitendinosus with 8.5 lb. and the iliotibial band with 13.6 lb. All these differences were statistically significant (p less than 0.01). The tension that needs to be applied to a graft during an anterior cruciate ligament reconstruction appears to be tissue specific. It is hoped that precise intraoperative tensioning of anterior cruciate ligament grafts will lead to more reproducible anterior cruciate reconstruction results.

A biomechanical comparison of different surgical techniques of graft fixation in anterior cruciate ligament reconstruction

Different surgical methods of graft fixation in ACL reconstruction were examined to determine the effects on mechanical properties of the reconstructed ACL. Ten human cadavers were used in this study. Six different types of grafts were studied. The tendon grafts were removed from each cadaver and fixed to femurs and tibias as ACL substitutes with different surgical fixation methods, leaving femur-reconstructed graft-tibia preparations. The surgical techniques used were staple fixation, tying sutures over buttons, and screw fixation. In the latter, the screws were introduced through femoral and tibial drill holes from the outside in order to achieve interference fit as described by Lambert. Tensile testing demonstrated that the original ACL is significantly stronger than the graft used for reconstruction in linear load, stiffness, and maximum tensile strength. All of the failures of the reconstructed ACL grafts occurred at the fixation site, indicating that the mechanically weak link of the reconstructed graft is located at the fixation site. Among the different methods of fixation, one-third of the patellar tendon secured with a cancellous screw, especially with a custom designed large diameter screw, showed significantly higher values. Although many other factors affect the success of ACL reconstruction, our study indicates that the method of surgical fixation is the major factor influencing the graft's mechanical properties in the immediate postoperative period.

Evaluation of residual instability after arthroscopic meniscectomy in anterior cruciate deficient knees

Forty-five patients who underwent a partial meniscectomy in an anterior cruciate deficient knee were followed from 2 to 9 years. The average age at the time of the meniscectomy was 28.6 years. The majority of the patients were injured in recreational athletics. The subjects were evaluated preoperatively by a questionnaire and clinical examination, both of which were repeated at followup. The efficacy of the postsurgical rehabilitation was monitored with measurement of quadriceps and hamstring strength on the Cybex Dynamometer. All of the patients had a KT-1000 knee ligament arthrometer test at followup that was compared with the clinical examination. Sixty-five percent of the subjects (13 of 20) with a Lachman and pivot shift of +1 returned to their previous activity level without limitation. Of the patients with a KT-1000 compliance index of 1 mm, 70% (11 of 17) returned to the same athletic level. However, only 20% (2 of 11) of the patients with a clinical instability greater than +1 or a compliance index of 2 mm were able to perform without limitation. The location of the meniscal tear did not correlate with the functional outcome. Six patients required ACL reconstruction.

Derotation brace and knee function in patients with anterior cruciate ligament tears

In this article we have tested a ready-made brace to evaluate whether it could improve function in the anterior cruciate ligament injured patient. All patients had their full extent of injury mapped out at arthroscopy. We believe that arthroscopy before treatment for a torn anterior cruciate ligament injury is necessary in order to treat meniscus lesions that could interfere with the rehabilitation. In this study, 26 patients were unstable with a positive pivot-shift, and 16 patients were operated on and thus stable. All patients performed a performance test with and without the brace in a randomized order. Before the start of the investigation, we postulated that patients with a quadriceps atrophy who were unstable would improve their function with the derotation brace. We could not find any effects of the brace in this study. The brace did not significantly improve function in the group of patients who were unstable with a quadriceps atrophy. On the other hand, the brace did not impair function in the patients. We conclude that to be able to improve knee function in the unstable knee, other modes of treatment than bracing are necessary. Bracing should be seen as a complement to these other treatments.

Anterior cruciate ligament arthroplasty

A unique augmentation arthroplasty has evolved from a retrospective review of 150 anterior cruciate ligament (ACL) repairs, extracapsular substitutions, and pes anserine transfers. This coincided with a proposed pathologic relationship seen in surgical exposures of the femoral intercondylar notch. From 1976 to 1983, 544 cases with known ACL insufficiency were selected for study. In 397 subsequent anterior cruciate stabilizations arthroplasties were performed. Patients with less than a 2 year followup were not included in this retrospective study. One hundred nine arthroplasties are reported: 80 isolated ACL tears and 29 multiple ligament injuries. Statistically significant relationships between elapsed time from ACL tear to surgery and meniscal tears, and elapsed time and degenerative changes in the articular surfaces were seen. Surgical technique was arthroplasty, graft harvest, graft placement, graft set, and postoperative care. Functional score followup has occurred for an average of 3 years (range 2 to 5 years). No patient has failed to return to his or her original sport or occupational demands. Pivot shift, disengagement, or spontaneous rupture of the arthroplasty has not occurred postoperatively. Full participation has occurred with bilateral ACL arthroplasties and arthroplasty performed for previous intraarticular augmentation failure. The operative success in the preliminary follow-up period was based on: ligamentous substitution, anatomical placement, femoral intercondylar notch compliance in full range of motion, revascularization of the ligament substitute, and histologic support of the procedure.

Two-year follow-up of conservative treatment of knee ligament injuries

Sixteen patients with old knee ligament injuries and symptoms of instability or pain were treated with a 3-month thigh muscle strength training program. Nine patients had a tear of the anterior and six patients a tear of the posterior cruciate ligament. One patient had a tear of both cruciates. Knee function was determined with a knee scoring scale, and thigh muscle strength with a Cybex-II dynamometer before training, after 1 and 3 months of training, and at a late follow-up after 2 years. Ten patients who increased their quadriceps strength by more than 15 per cent increased their score over 30 per cent. Three patients who showed a minor increase in strength did not increase their score significantly. Three patients did not increase their strength at all. All of these admitted a reluctance to train. Four patients, all with anterior cruciate ligament tears, were operated on after the 3-month training period. All four patients increased their strength. Two of them increased their functional score also, but they strove for a very high activity level and were therefore operated on. The other two patients had no symptomatic relief and were therefore also operated on. Improvements in muscle strength and knee function were unchanged at the 2-year follow up. Before planning a knee ligament reconstruction, a period of strength training is recommended.

Symposium on sports medicine: Part I. Current concepts in the treatment of ligamentous instability of the knee

Ligamentous injury to the knee remains a difficult diagnostic and therapeutic problem. Modern knowledge of the pathoanatomy of various instability problems has made diagnosis of injuries to key structures possible. Aggressive treatment, nonoperative and operative, has vastly improved the prognosis for return to stable function of the knee.

The Lenox Hill derotation brace in chronic post-traumatic instability of the knee

Nine Lenox Hill derotation knee braces have been fitted for post-traumatic ligamentous instability of the knee. Eight of the patients found it an effective appliance for preventing their knees giving way, and wear it regularly. We would recommend this brace for cases of post-traumatic instability of the knee when the ligaments are at fault and provided that internal derangements such as meniscal tears or loose bodies have already been treated.

Anterior cruciate-deficient knees: a review of the literature

Injury to the anterior cruciate ligament may lead to functional instability, meniscal injury, and premature degenerative changes of the knee or, if treatment and rehabilitation are carried out carefully, to a functionally stable knee with no premature degenerative changes. Unfortunately, the complex anatomy of the three fiber bundles, consisting of multiple collagenous strands, which constitutes the anterior cruciate ligament combined with variation of injuries to the ligament, with or without injury to other structures of the knee, makes any standardization of surgical treatment difficult. In this paper, we review the biomechanics of the knee, the anatomy and vascularization of the anterior cruciate ligament, the healing characteristics of ligamentous material, and the types of surgical repair that have appeared in recent articles. Those repairs can be divided into direct repair, extraarticular substitution and intraarticular augmentation, freeze-dried fascia lata allografts, and temporary supportive prosthesis such as carbon fiber. Essential to the success of any surgical repair of the anterior cruciate-deficient knee is a prolonged, carefully organized rehabilitation program that allows adequate healing and strengthening of the ligament before it is used normally again. The patient's clear understanding of the importance of a prolonged rehabilitation is best established before the surgical procedure is done.

Reconstruction procedures for anterior cruciate ligament insufficiency: a computer analysis of clinical results

A pre- and postoperative study of 205 patients who had surgical reconstruction of the anterior cruciate ligament (ACL) of the knee was evaluated with the use of a prototype computer program. An average followup of 4.1 years revealed a 27% improvement in subjective complaints and a 8% improvement in objective findings. The anterior drawer test was improved 25% and subluxation of the lateral tibial plateau (ALRI) was improved 118% correlating highly (P less than 0.001) with a good result. Seventy-four percent of patients had undergone medial meniscectomy, 58% lateral meniscectomy, and 41% had both menisci removed at followup after reconstruction. Ninety-two percent of the 121 patients responding to a final subjective complaint evaluation felt that their knee was significantly improved (average 6.1 years after reconstruction). The computer demonstrated a wide variation in the results of reconstruction within the intraarticular, extraarticular, and combined groups. The addition of associated procedures to the main reconstructive procedure significantly affected the results. This study reveals improvement of subjective complaints and objective findings after reconstructing the anterior cruciate ligament and proposes the use of computer analysis for specific evaluation of different procedures.

Incidence of fractures on the distal radius and proximal femur: comparison of patients in a mental hospital and the general population

A statistically significant increase in the incidence of fractures of the distal radius was found in the general population of southern Sweden during recent decades. As regards fractures of the proximal femur, an increase in the incidence of trochanteric fractures was observed only in women. In male patients at a mental hospital the fracture rate of the distal radius was the same as in the general population but the fracture rate of the proximal femur was about twelve times higher. In female patients at the same mental hospital the fracture rate of the distal radius was three times greater and that of proximal femur about seven times greater than that of the general population. This difference may not only be due to an increased skeletal fragility in patients in mental institutions but may also suggest poorer protective mechanisms against falls. Undiagnosed cardiovascular or neurological diseases, for example intermittent cardiac arrhythmia or transient cerebral ischaemic attacks, may cause falls. Early diagnosis and treatment of such diseases may reduce the number of fractures of the proximal femur.