Infrapatellar contracture syndrome. An unrecognized cause of knee stiffness with patella entrapment and patella infera

A biomechanical analysis of matched bone-patellar tendon-bone and double-looped semitendinosus and gracilis tendon grafts

Biomechanical testing was done on 15 matched pairs of central-third bone-patellar tendon-bone and double-looped semitendinosus-gracilis grafts harvested from 15 cadaveric knees. Load to failure, composite graft stiffness, and the modulus of elasticity were calculated for each graft. Specimens were from 2 female and 13 male donors (average age, 40 years; range, 17 to 53). Average load to failure for the patellar tendon grafts was 1784 N (+/- 580), compared with 2422 N (+/- 538) for the hamstring tendon grafts (significantly different). There was no statistically significant difference in stiffness between grafts (patellar tendon, 210 N/mm; hamstring tendon, 238 N/mm). The elastic modulus was 225 MPa (+/- 129) for the patellar tendon grafts and 145 MPa (+/- 58) for the hamstring tendon grafts (significantly different). The average cross-sectional area for the hamstring tendon grafts was 57 mm2, compared with the 45 mm2 for the patellar tendon grafts. The hamstring tendon grafts were significantly stronger than the matched central-third patellar tendon grafts, but the two grafts were similar in stiffness. The patellar tendon grafts had a higher modulus than the hamstring tendon grafts.

Patellar tendon augmentation after removal of its central third limits joints tissue changes

The central third of the patellar tendon is commonly used to reconstruct the injured anterior cruciate ligament. Some studies have noted changes in joint tissues following this procedure. It has been postulated that these changes may be associated with increased stress on the remaining tendon following harvest of the graft. In our study, the central third of the patellar tendon was excised in three groups of rabbits. The central tendon defects in two of the three groups were fitted with different augmentation devices to augment the host tendon during the healing process. All rabbits followed a daily treadmill exercise regimen for 12 weeks following the operation. Biomechanical testing of the tendon revealed that in nonaugmented tendons the cross-sectional area and the length of the patellar tendon significantly increased 112 and 16%, respectively. There was histological evidence of host-tendon remodeling throughout the cross section and extensive fibrosis in the infrapatellar fat pad. Augmentation of the tendon significantly reduced these changes, with the least change noted in the group with the greatest augmentation. The rabbits with augmentation devices retained tendon dimensions similar to those of the contralateral intact tendon, and tendon remodeling occurred only in the defect area. The rabbits with augmentation devices exhibited little to no fibrosis of the fat pad. Structural properties of augmented and nonaugmented tendons were similar despite the size differences, indicating higher tissue quality in the augmented tendons. This study suggested that complications of the knee joint (i.e., tendon proliferation and fat pad fibrosis) noted after anterior cruciate-ligament reconstruction with the autogenous patellar tendon may be limited by the implantation of an augmentation device.

Revision anterior cruciate ligament surgery

An increasing number of revision ACL reconstructions are being performed each year. Revision ACL surgery is challenging and cannot be approached in the same manner as primary ACL surgery. Successful revision ACL surgery requires a detailed history, a comprehensive physical examination, appropriate radiologic studies, and careful preoperative planning. The results of revision ACL surgery do not equal the results of primary ACL surgery, and this should be explained to the patient prior to surgery. In order to avoid repeating errors that led to failure of the primary reconstruction, the etiology of the primary failure must be clearly understood before proceeding with the revision procedure. Although graft failure is the most common reason for failure of the original reconstruction and revision surgery, other non-graft-related problems, such as loss of motion, extensor mechanism dysfunction, and degenerative arthritis, can also result in an unsatisfactory outcome and residual complaints. Errors in surgical technique, specifically nonanatomic graft placement and failure to address associated ligamentous injuries at the time of the original procedure, are responsible for graft failures in most reported series. Preoperative planning must address the issues of graft selection, skin incisions, hardware removal, tunnel placement, graft fixation, and associated ligamentous injuries. Loss of motion and in some cases enlarged bone tunnels may require a staged approach. Because of the weaker initial graft fixation, laxity of secondary restraints, the potential need to address associated ligamentous injuries, and the presence of more significant articular cartilage changes, an accelerated rehabilitation program is inappropriate in most revision cases. Successful revision ACL surgery requires a motivated and compliant patient, a well thought out plan, and an experienced surgeon who is knowledgeable and proficient with a variety of different surgical techniques, graft sources, and graft fixation techniques.

Objective factors affecting overall subjective evaluation of recovery after anterior cruciate ligament reconstruction

The goal of this prospective study was to determine how objective measurements affect the overall subjective evaluation of recovery after anterior cruciate ligament (ACL) reconstruction and to evaluate the effects of graft material, residual instability and sporting activity on patient satisfaction. Ninety-seven patients with unilateral ACL injuries whose ACL was reconstructed using either a multi-strand semitendinosus (ST) graft or a central-third bone-patellar tendon-bone (BTB) graft were followed for an average of 30 months. An "overall subjective recovery score" was derived from the patients' evaluation of function of the operated knee as a percentage of the unoperated knee. The mean overall subjective recovery score at follow-up was 80% (range, 20% to 100%). This study strongly suggested that integrity of the knee extension mechanism, that is, good recovery of knee extension strength with achievement of full extension and no problems in the patellofemoral joint, is the most important factor in patient satisfaction after ACL reconstruction.

Effects of patellar tendon adhesion to the anterior tibia on knee mechanics

The effects of patellar tendon adhesion on the knee extensor mechanism and on the kinematics and contact areas for both the patellofemoral and tibiofemoral joints were determined for five cadaveric knees in an open kinetic chain testing configuration. Patellar tendon adhesion decreased the distance from the inferior patellar pole to the tibial tuberosity, effectively creating patella infera. When compared with the controls, knees with adhesion had medial and distal translation of the patella, as well as increased patellar flexion. Although the patellar articular contact location shifted distally, the overall contact area did not change significantly. For the tibia, adhesion resulted in significant medial, proximal, and anterior translation, and internal rotation. Adhesion also resulted in a posterior shift of the tibial contact location. For the extensor mechanism, adhesion decreased the knee extension force created by the quadriceps muscle on the tibia, indicating a decrease in the effective moment arm of the extensor mechanism. Furthermore, as a result of patellar tendon adhesion, the angle formed by the quadriceps and patellar tendons decreased, suggesting an increase in patellofemoral joint reaction force with adhesion. The increased patellofemoral joint reaction force and the altered contact location may be related to anterior knee pain after knee trauma and knee surgery. Therefore, patients should be observed for subtle patella infera, which may indicate patellar tendon adhesion.

Medial soft tissue restraints in lateral patellar instability and repair

This study was undertaken to evaluate the medial ligamentous stabilizers of the patella in restraining lateral displacement and to assess their relative contribution after individual repair. Seventeen fresh frozen human anatomic specimen knee joints were studied. The specimens were loaded onto a testing instrument that was designed to measure the compliance of the medial and lateral patellar restraints in the coronal plane. Two different cutting and repair sequences were used to test the individual contributions of the patellar ligaments. The medial patellofemoral ligament was found to be the major medial ligamentous stabilizer of the patella. Isolated release resulted in a 50% increase in lateral displacement, and isolated repair restored balance to the patella. In addition, the patellotibial and patellomeniscal ligament complex played an important secondary role in restraining lateral patellar displacement. Isolated repair of these ligaments restored balance to near normal levels. The medial patellofemoral retinaculum played only a minor role in patellofemoral instability. Proximal realignment or medial ligament repair for patellofemoral instability specifically should address repair of the deep layers that contain the restraints to lateral patellar displacement. Failure to include these structures in repair, especially of the medial patellofemoral ligament, may lead to persistent or recurrent instability.

The effects of removal and reconstruction of the anterior cruciate ligament on patellofemoral kinematics

Patellofemoral pain may be associated with anterior cruciate ligament deficiency or may occur after anterior cruciate ligament reconstruction. We investigated the effects of the removal and reconstruction of the anterior cruciate ligament on the kinematics of the tibiofemoral and patellofemoral joints during physiologic levels of quadriceps muscle loads in seven cadaveric knees. A bone-patellar tendon-bone graft was used for intraarticular reconstruction of the anterior cruciate ligament. The spatial positions of the tibiofemoral and patellofemoral joints were measured between 0 degrees and 90 degrees of knee flexion in 15 degrees increments with a six degree-of-freedom digitizing system. Excision of the anterior cruciate ligament resulted in statistically significant increases in anterior tibial translation between 0 degrees and 90 degrees and valgus tibial rotation between 30 degrees and 90 degrees; intraarticular reconstruction returned these to levels not significantly different from those of the intact knee. Excision of the anterior cruciate ligament resulted in significant increases in lateral patellar tilt, ranging from 6.3 degrees to 9.0 degrees between full extension and 90 degrees of knee flexion, and in lateral patellar shift, ranging from 2.9 mm at 15 degrees of knee flexion to 5.9 mm at 90 degrees; intraarticular reconstruction returned these to levels not significantly different from those of the intact knee. Neither removal nor reconstruction of the anterior cruciate ligament significantly affected tibial internal-external rotation, patellar flexion, patellar mediolateral rotation, patellar anteroposterior translation, or patellar proximodistal translation.

Patella position and biomechanical properties of the patellar tendon 1 year after removal of its central third

OBJECTIVE: The aim of this study was to investigate how the removal of a patellar tendon graft for cruciate ligament reconstruction influences the mechanical properties of the remaining patellar tendon and the position of the patella at the knee joint. DESIGN: The experimental model of this in vivo study was the anterior cruciate ligament reconstruction in sheep. BACKGROUND: While the efficacy of a patellar tendon third as a ligament replacement has been extensively investigated, the consequences for the function of the remaining tendon and patella position remain unclear. METHODS: The central third of the patellar tendon from the right knees of 10 animals was removed for cruciate ligament replacement. One year postoperatively, the position of the patella within the joint and the stiffness and modulus of elasticity of the remaining tendon were compared with the non-operated contralateral controls. RESULTS: The patella position did not change in the operated knee joints in comparison with the controls. The cross-sectional area of the operated patellar tendon increased significantly by scar tissue formation at the defect site. CONCLUSION: Although the inferior mechanical properties of the scar tissue reduced the modulus of, elasticity of the tendon, the increase in cross-sectional area allowed it to develop a structural stiffness similar to the control tendons. RELEVANCE: The central third of the patellar tendon is often used for ligament replacement. Resulting biomechanical and structural changes in the remaining patellar tendon have not been previously reported using an in vivo animal model. The recovery of the biomechanical properties of the partially resected tendons allows for continued function.

Patellar strain and patellofemoral contact after bone-patellar tendon-bone harvest for anterior cruciate ligament reconstruction

OBJECTIVE

To characterize the morbific consequences of harvesting a patellar tendon graft for use in reconstructing the anterior cruciate ligament (ACL) of the knee, specifically, (1) to measure changes in patellar strain and patellofemoral contact due to graft harvest, (2) to evaluate the ability of bone-grafting the patellar defect to mitigate these effects, and (3) to characterize failure of the extensor mechanism after harvest of a patellar tendon graft.

DESIGN

Twenty-two cadaver knee joints were tested before and after harvest of a patellar tendon graft and after filling the patellar defect with polymethylmethacrylate to simulate a healed bone graft, Knees were positioned in 30 degrees, 60 degrees, and 90 degrees flexion and loaded while measuring axial strain in the anterior patella and patellofemoral contact. Knees were then loaded to failure.

RESULTS

Harvest of the graft produced increases in axial strain at all flexion angles. Filling the defect restored axial strain to normal values. Patellofemoral contact in the presence of a defect, either filled or empty, was not different from contact for intact patellae. Most knees failed by transpatellar fracture; mean extension moment at failure was 112.8Nm. The best predictors of failure were age and gender.

CONCLUSION

Patients undergoing ACL reconstruction with a patellar tendon graft are at increased risk of anterior knee pain and disruption of the extensor mechanism. Bone-grafting the patellar defect created by graft harvest can reduce these risks. Our findings underscore the importance of carefully controlled rehabilitation and suggest that if an accelerated program of rehabilitation is anticipated, the patellar defect should be bone-grafted. Older patients, particularly women, are at increased risk of catastrophic failure of the knee extensor mechanism after ACL reconstruction using patellar tendon graft.

Preventing anterior knee pain after anterior cruciate ligament reconstruction

We studied a group of 602 patients who had anterior cruciate ligament reconstructions between 1987 and 1992. An autogenous patellar tendon graft was used, regardless of preexisting patellofemoral pain or chondromalacia. The surgeon and rehabilitation protocol were the same for all patients, with emphasis on obtaining full knee hyperextension postoperatively. All patients were evaluated by a questionnaire designed to determine the incidence and severity of anterior knee pain as it relates to sporting or daily living activities, prolonged sitting, stair climbing, and kneeling. Range of motion for the study group was recorded during physical examination. We compared the findings with those from a control group of 122 patients who had no previous knee injury. The study group reported a mean score of 89.5 +/- 12.5, compared with 90.2 +/- 12.3 in the control group. Both the operative and control groups reported little or no symptoms during sporting activities (94% and 92%, respectively). No differences were noted with respect to the other activities surveyed. These results demonstrate that anterior knee pain after anterior cruciate ligament reconstruction is not an inherent complication associated with patellar tendon harvesting. We suggest that the increased incidence of anterior knee pain with an autogenous patellar tendon graft can be prevented by obtaining full knee hyperextension postoperatively. This goal can be achieved through preoperative rehabilitation and a postoperative protocol emphasizing early restoration of full knee hyperextension.

Quantitative analysis of synovial fibrosis in the infrapatellar fat pad before and after anterior cruciate ligament reconstruction

We performed quantitative analysis of synovial fibrosis in the infrapatellar fat pad in 26 patients who underwent arthroscopically assisted anterior cruciate ligament reconstructions. Twelve patients underwent reconstruction with patellar tendon autografts, and 14 had reconstructions with semitendinosus and gracilis tendon autografts. Synovial samples were obtained at the time of reconstruction from 10 patients and at second-look arthroscopy from all 26 patients. Sections from quick-frozen samples were stained with either hematoxylin and eosin or Fast green and Sirius red. We used sodium hydroxide in absolute methanol to elute the Fast green and Sirius red stains, and the total collagen content of each section was estimated by measuring the optical density of the eluted solution. The volume of each section was determined on a computer using an imaging program, and collagen content per unit of tissue was calculated. Median collagen content was 15.3 micrograms/mm3 for the preoperative samples, 25.1 micrograms/mm3 for the group with patellar tendon autografts, and 27.1 micrograms/mm3 for the group with hamstring tendons autografts. Analysis of preoperative and postoperative paired samples revealed a significant increase in synovial collagen after anterior cruciate ligament reconstruction. We observed increased fibrosis in patients who had pain on exertion or stiffness in squatting after the reconstructive surgery.

Classification and management of arthrofibrosis of the knee after anterior cruciate ligament reconstruction

We report 72 patients with disabling knee arthrofibrosis who were treated at our clinic. All patients had painful restriction of extension or limitation of both extension and flexion that had persisted despite physical therapy. The level of arthrofibrosis was categorized into one of four types: Type 1 (25 patients), < 10 degree extension loss and normal flexion; Type 2 (16 patients), > 10 degree extension loss and normal flexion; Type 3 (15 patients), > 10 degree extension loss and > 25 degree flexion loss with a tight patella; and Type 4 (16 patients), > 10 degree extension loss, 30 degrees or more flexion loss, and patella infera with marked patellar tightness. All patients were treated with outpatient arthroscopic surgery. Anterior scar resection down to the proximal tibia was required for all patients with Types 2, 3, and 4 arthrofibrosis. Notchplasty was performed when necessary. Medial and lateral capsular releases and knee manipulation were required for patients with Type 3 or 4 arthrofibrosis. Postoperatively, all patients with Types 2, 3, and 4 arthrofibrosis were treated with outpatient serial extension casting. At the time of latest followup (28 to 115 months), the mean improvement of range of motion was as follows: Type 1, 7 degrees of extension; Type 2, 14 degrees of extension; Type 3, 13 degrees of extension and 28 degrees of flexion; and Type 4, 18 degrees of extension and 27 degrees of flexion. Improvement was also found for the mean stiffness, self-evaluation, functional activity, and Noyes knee scores in all groups.

Late patellar tendon ruptures after removal of the central third for anterior cruciate ligament reconstruction. A report of two cases

Patellar tendon rupture after removal of the central third for ACL reconstruction is a rare complication. Only nine cases have been previously reported, and all of these occurred within the first 10 months after surgery. We report two cases of late patellar tendon ruptures occurring at more than 3 and 6 years, respectively, after surgery. A review of the literature has suggested but not conclusively supported that devascularization, an alteration in tendon healing and remodeling, or injury to the remaining tendon at the time of graft harvest may be possible causes of this rare complication. Biopsy tissue from any future patellar tendon ruptures after removal of its central third could contribute to a better understanding of this anomaly.

Anterior cruciate ligament reconstruction with multistranded autogenous semitendinosus tendon

We evaluated 41 knees 24 to 48 months after anterior cruciate ligament reconstruction was performed using multiple autogenous semitendinosus tendons. The ipsilateral free semitendinosus tendon was tripled or quadrupled to make a graft 7 to 10 mm in diameter and more than 60 mm long. When the diameter of the graft was less than 7 mm, an ipsilateral doubled gracilis tendon was also used (in seven cases). Twenty-three patients (56%) returned to their preinjury activity levels. According to the patients' subjective assessment, 34 (83%) graded themselves as normal or nearly normal. No patient reported giving way of the knee or limitation of knee motion. The average anterior laxity difference between the involved knee and contralateral uninjured knee was 1.5 mm at 200 N. Twenty-nine patients (71%) demonstrated an anterior laxity difference of 3 mm or less when the involved knee was compared with the contralateral uninjured knee. Quadriceps muscle strength was 90% compared with the contralateral healthy limb, and hamstring muscle strength was equivalent to the contralateral limb. In our study, tripled or quadrupled semitendinosus free tendons were excellent anterior cruciate ligament grafts for restoring knee stability, recovering thigh muscle power, and preserving knee motion.

Achieving full range of motion after anterior cruciate ligament reconstruction

A review of 119 consecutive anterior cruciate ligament reconstructions showed that the time from injury to surgery (early versus delayed) did not make a difference in obtaining full range of motion. Only patients with late surgery had a slight decrease in range of motion. Followup data were obtained for 111 reconstructions. Twenty-one were early surgeries (1 to 14 days), 22 were delayed surgeries (15 to 28 days), and 68 were late surgeries (more than 28 days). The patients involved in the 21 early surgeries obtained 0 degree of knee extension or better and 135 degrees of knee flexion or better. The patients involved in the 22 delayed reconstructions reached 0 degree of knee extension or better and 135 degrees of flexion or better. Among the patients with the 68 late surgeries, 93% of the knees reached 0 degree of extension or better and all reached at least 135 degrees of flexion. The five patients who did not achieve full knee extension had extension loses less than 4 degrees. All 111 reconstructions were determined stable when full range of motion was achieved based on clinical examination, which included the Lachman test, anterior drawer test, pivot shift, and KT-1000 arthrometer when appropriate.

Arthroscopic arthrolysis for flexion contracture following intraarticular reconstruction of the anterior cruciate ligament

This article describes the surgical technique and expected results for arthroscopic arthrolysis for the treatment of flexion contracture following anterior cruciate ligament (ACL) reconstruction. The technique emphasizes a systematic approach to the surgical procedure followed by an intensive rehabilitation program. The results in 11 patients treated with this technique are reviewed. They averaged 12.6 months from the index ACL reconstruction. Despite extensive physical therapy, their mean preoperative flexion contracture was 19 degrees, mean total range of motion was 94 degrees, and mean preoperative Lysholm score was 67. At a mean follow-up of 22 months following arthrolysis and physical therapy, mean flexion contracture improved to 2 degrees, total range of motion improved to 125 degrees, and mean Lysholm score improved to 94.

Patellar height ratios. A comparison of four measurement methods

Three blinded observers on three separate occasions calculated four commonly employed patellar height ratios on the knees of 15 patients who had three lateral radiographs each. The observers used the same measurement instrument, a hand-held goniometer ruler, to determine the relative reliability of each patellar height ratio. The measurements by the three observers were examined, and the error and reliability of the four methods of measurement were tested statistically. Among the four methods of measuring patellar height that we studied, the Blackburne-Peel method most consistently reproduced the patellar height index. Interobserver measurement error averaged 0.06 for all ratios. Values greater than 0.06 represented real patellar height changes. The ratios were not significantly affected by the change of knee flexion angle from 30 degrees to 50 degrees. Side-to-side patellar height measurement differences averaged 0.16, which suggests that the healthy contralateral limb is not reliable as a control. Mild arthritic changes decreased variability of measurements by an average of 24% because small osteophytes better defined the articular margins of the patella.

A prospective, randomized study of three operations for acute rupture of the anterior cruciate ligament. Five-year follow-up of one hundred and thirty-one patients

A five-year, prospective, randomized follow-up study was done to compare three methods for repair of a rupture of the anterior cruciate ligament of the knee; acute primary repair (Group 1), acute repair with a synthetic ligament-augmentation device (Group 2), and acute repair augmented with an autologous bone-patellar ligament-bone graft (Group 3). One hundred and fifty patients who had an acute rupture of the anterior cruciate ligament were randomized to one of the three repair groups, with fifty patients in each group. The patients were between sixteen and fifty years old (mean, twenty-nine years old). All patients had the operation within ten days after the injury. The rehabilitation protocol was identical for each group. The patients were evaluated prospectively at one, two, and five years with use of the Tegner scoring system for level of activity and the scoring system of Lysholm and Gillquist for function, and the stability of the knee was assessed with clinical examination and with use of the KT-1000 arthrometer. One hundred and thirty-one patients completed the study and ten other patients were known to have had a failure of the procedure, a 94 percent rate of follow-up. All three groups had a lower level of activity at the five-year follow-up evaluation than they had had before the injury. The patients who had had augmentation with a patellar-ligament graft had a significantly higher mean level of activity at two years than those who had had non-augmented repair with (p = 0.002) and those who had had repair with a synthetic ligament-augmentation device (p = 0.01). They also had a significantly higher mean level of function at two years than those who had had non-augmented repair (p = 0.0001) and those who had had repair with a synthetic ligament-augmentation device (p = 0.03) and a significant higher mean level of function at five years than those who had had non-augmented repair (p = 0.004). The ability to attain full extension improved significantly in all three groups during the five-year follow-up period; the highest gains occurred in the group that had had augmentation with a patellar-ligament graft. Rotatory and anterior instability progressively increased during the follow-up period for all three groups. At one, two, and five years, the knees that had had repair with a patellar-ligament graft were significantly more stable than those that had had non-augmented repair and those that had had repair with a ligament-augmentation device (p < 0.0001 to p = 0.03). The findings of this study reinforce the conclusions of our two-year follow-up report that a non-augmented primary repair should not be performed, a repair with a ligament-augmentation device has an unacceptably high rate of failure (more than one-third of the patients), and a repair that is augmented with the patellar ligament has the best outcome.

Light and scan electron microscopic analysis of cyclops syndrome: etiopathogenic hypothesis and technical solutions

The loss of range of motion after anterior cruciate ligament (ACL) reconstruction is one of the most common and most challenging complications of this kind of surgery. Recently, an intercondylar notch fibrous proliferation, called cyclops syndrome because of its arthroscopic appearance, has been identified as one of the specific causes of loss of extension. The incidence of cyclops syndrome is 2%-4% [17, 18], but there is still no understanding of its etiology. We speculate on the etiology and suggest some technical solutions to reduce this complication. In 180 patients submitted to arthroscopic ACL reconstruction with patellar tendon, we observed in 4 cases a fibrous nodule adherent to the neoligament that caused a loss of extension between 12 degrees and 17 degrees. In all cases, arthroscopic removal of this nodule solved completely the loss of articular motion. The nodules were subjected to light and scanning electron microscope evaluation. We observed numerous, newly formed vessels in all 4 nodules. These vessels were made up of hyperplastic and hypertrophic cells and were surrounded by bundles of disorganized fibrous tissue. No inflammatory cells or bone or cartilaginous tissue was observed. We hypothesize a microtraumatic genesis for cyclops syndrome. Repeated microtraumas expose the graft collagen fibers, which can lead to productive inflammatory process and thence to the formation of the cyclops nodule. We suggest some technical solutions to avoid graft impingement with the notch and with the tibial bone tunnel.

Prospects for gene therapy in sports medicine

For the orthopedic sports medicine physician soft tissue injuries often present the greatest clinical problems. Not only do many of the most frequently injured tissues, such as the cruciate ligaments and articular cartilage, have very limited capabilities for spontaneous repair, but they also respond poorly to surgical or nonsurgical intervention. In this article we try to define the role of growth factors in these conditions and to outline concepts for future treatment based upon modulation of the native repair response. We suggest that gene transfer could improve the management of such injuries, particularly when used as vehicles for the targeted delivery of growth factors. The concept of gene therapy in orthopedic sports medicine can be extended to include disorders that present as laxity or mechanical weakness of ligaments. We speculate that subtle genetic differences between individuals may account for those who appear to be injury prone. In these cases it is likely that genes encoding the structural macromolecules of the matrix are defective. Local gene supplementation in such cases could be useful in the future.

Role of posterior capsulotomy for the treatment of extension deficits of the knee

Chronic flexion contracture of the knee is difficult to treat, especially in cases with long-standing extension deficits and with generalised arthrofibrosis. We present a technique combining arthroscopic or open anterior debridement with a posterior capsulotomy. This capsulotomy is performed via a posteromedial incision and a posteromedial arthrotomy. All scar tissue is resected, and the entire posterior capsule is detached from its femoral attachment. Of 24 patients treated with arthroscopic arthrolysis and posterior capsulotomy from 1989 to 1993, 21 were reviewed with a mean follow-up of 18 months (range 6-38 months). The mean extension deficit preoperatively was 17 degrees (range 10-30 degrees), and symptoms and persisted from 6 months to 7 years. Extension improved to a mean value of 2 degrees; no patient had more than 5 degrees of extension deficit at follow-up. The knee function improved significantly (Lysholm Score preoperative 62, postoperative 88, Tegner Scale preoperative 2.2, postoperative 4.0). No neurovascular complications were observed, and we conclude that posterior capsulotomy is a safe and efficient adjunct procedure to anterior arthrolysis and is indicated in cases with chronic flexion contracture.

Immunohistologic analysis of synovium in infrapatellar fat pad after anterior cruciate ligament injury

To clarify the natural course of synovitis after anterior cruciate ligament injury, we took synovial tissues at various periods after injury and analyzed them immunohistologically. Twelve patients with isolated anterior cruciate ligament injuries participated in the study. Inflammation intensity was graded semiquantitatively based on the following parameters: synovial lining cell depth, synovial hyperplasia, vascular hyperplasia, lymphocyte infiltration, and the expression of cell adhesion molecules. The expression of fibrogenic cytokines and the degree of fibrosis were also investigated to elucidate the mechanisms of arthrofibrosis. The results demonstrated that synovitis in the infrapatellar fat pad subsides within 3 months after injury with the progression of fibrosis. Fibrogenic cytokines, platelet-derived growth factor and transforming growth factor-beta, were detected at fibrotic sites, suggesting their involvement in arthrofibrosis. An increased incidence of arthrofibrosis recently has been recognized to occur when anterior cruciate ligament reconstruction is performed within several weeks after injury. We speculate that when anterior cruciate ligament reconstruction is performed during the stage of acute synovitis, the operation may further promote the synovitis, accelerating the arthrofibrotic reaction. Waiting to perform the anterior cruciate ligament reconstruction until the synovitis resolves may possibly decrease the motion problems seen postoperatively.

Early versus late reconstruction for anterior cruciate ligament rupture. Results after five years of followup

We investigated the clinical and laxity testing results at 5 years' followup in patients who had early or late anterior cruciate ligament reconstruction. Twenty-three patients (Group I) were treated within 15 days of injury. Fifty-nine patients (Group II) were treated more than 3 months after injury. Patellar tendon reconstruction and fascia lata graft augmented with a ligament augmentation device were the techniques used in both groups. According to the International Knee Documentation Committee rating scale, 17 patients in Group I and 38 patients in Group II had satisfactory results. The Lysholm score was good in all Group I patients and in 55 Group II patients. Flexion-extension deficits were comparable for both groups. Eighteen patients (78%) in Group I demonstrated satisfactory results according to the KT-2000 arthrometer testing, compared with 44 (75%) in Group II. No associated lesions were present in 12 (52%) cases in Group I, compared with 26 (44%) cases in Group II. Return to sports at the preoperative level was obtained by 21 (91%) patients in Group I, compared with 42 (71%) in Group II. The patients who had reconstruction during the early phase returned to sports activities sooner and had better clinical and laxity testing results.

Graft site morbidity with autogenous semitendinosus and gracilis tendons

To distinguish between morbidity caused by harvesting semitendinosus and gracilis tendons and morbidity associated with anterior cruciate ligament reconstruction surgery, we performed a prospective randomized study using 65 patients who underwent anterior cruciate ligament reconstruction using these tendons. The patients underwent either contralateral (N = 34) or ipsilateral (N = 31) graft harvest. For the nonoperated knees in the ipsilateral harvest group, isometric and isokinetic strength of the quadriceps and hamstring muscles increased to approximately 120% of the preoperative value at 12 months after surgery. Compared with these knees, the tendon harvest did not affect quadriceps muscle strength at all. However, harvest did decrease hamstring muscles strength for 9 months after surgery. The graft harvest in the knees with anterior cruciate ligament reconstruction also did not significantly affect quadriceps muscle strength, but it did significantly decrease hamstring muscles strength only at 1 month. Activity-related soreness at the donor site was rarely restricting and resolved by 3 months. This study demonstrated that the semitendinosus and gracilis tendon graft is a reasonable choice to minimize the donor site morbidity in ligament reconstruction using autografts.

Assessment of patellar height after autogenous patellar tendon anterior cruciate ligament reconstruction

In this study, we sought to determine if a significant change in patellar height occurs after autogenous patellar tendon anterior cruciate ligament (ACL) reconstruction at our clinic. In a series of 71 patients (52 males and 18 females; average age: 22 years; range: 12 to 41) randomly selected, all had undergone an identical autogenous patellar tendon ACL reconstruction, by the same surgeon, and followed the same postoperative accelerated rehabilitation program. All patients had standardized preoperative and postoperative lateral knee radiographs. The patellar tendon length as well as the patellar height and ratio of Blackburne and Peel were measured by the same person for all subjects. The length of the patellar tendon shortened by an average of 0.4 mm (range: 6% lengthening to 12% shortening) which is less than 1% and not statistically significant (P = .068). The Blackburne and Peel ratio for patellar height decreased by 1%, which was also not statistically significant (P = .060). The evidence obtained from this study indicated no significant change in patellar height after autogenous patellar tendon ACL reconstruction combined with postoperative accelerated rehabilitation and no correlations with postoperative complications, secondary surgeries, timing of surgery, age, or anterior knee symptoms.

Ligament stability two to six years after anterior cruciate ligament reconstruction with autogenous patellar tendon graft and participation in accelerated rehabilitation program

We studied patients who participated in our accelerated rehabilitation program after anterior cruciate ligament reconstructive surgery to determine if they showed signs of patellar tendon graft stretching. This program initiated in 1987 emphasizes early full hyperextension, early weightbearing as tolerated, and closed-chain functional activities with rapid return to sports when the patient has attained full range of motion, approximately 65% of strength, and has accomplished the running and agility drills prescribed. A total of 209 patients met the criteria of KT-1000 arthrometer followup at the time full range of motion (5 degrees/0 degrees/135 degrees) was attained and at 2 years or more after surgery. The KT-1000 arthrometer manual maximum difference between the reconstructed and normal knees was used as the indicator of change in the graft length. All patients completed postoperative subjective questionnaires. The mean KT-1000 arthrometer value was 2.06 mm (SD, +/- 2.2) at full range of motion and 2.10 mm (SD, +/- 1.9) at more than 2 years of followup (P = 0.7961). The patients' subjective stability scores averaged 19.6 with 97% reporting no instability episodes. Based on our findings, we conclude that an accelerated rehabilitation program after this type of reconstruction does not affect long-term stability as measured by the KT-1000 arthrometer.

Results of surgical treatment of arthrofibrosis after ACL reconstruction

We prospectively studied 31 knee arthrolyses performed for loss of motion after intra-articular anterior cruciate ligament (ACL) reconstruction. The arthrolysis was performed on average 10.6 months after the reconstruction (range 4-25). Seven knees were localized forms. They were treated with arthroscopic removal of a fibrous nodule and scar tissue anterior to the ACL, which was preserved. Twenty-four knees were global forms and treated arthroscopically (14) or in open procedure (10). Suprapatellar, medial, and lateral gutter adhesions were sectioned, and fibrous tissue was removed from the anterior compartment. A posteromedial and/or posterolateral capsulotomy was necessary in 7 knees. The ACL graft was nonfunctional and/or malpositioned in 19 knees. The results were evaluated with the IKDC form with an average follow-up of 3.5 years (range 1.5-7). Preoperatively the localized forms had an average extension loss of 11 degrees and an average flexion loss of 14 degrees compared to the opposite knee. At follow-up all the knees were satisfactory for symptoms. All except one achieved a satisfactory motion (within 5 degrees of extension loss and 15 degrees of flexion loss) and a satisfactory final result. Global forms had a greater preoperative flexion loss (average 34 degrees) and extension loss (average 17 degrees). At follow-up 58% were satisfactory for symptoms and 71% for arc of motion. However, the final result was satisfactory in only 37%. In conclusion, local forms have a good prognosis. In global forms motion may be improved by surgery, but the final result is downgraded by symptoms. Arthrolyses performed within 8 months from index operation had a better outcome.

Anterior cruciate ligament patellar tendon reconstruction: it is probably better to leave the tendon defect open!

The purpose of our prospective study was to establish whether or not in anterior cruciate ligament (ACL) patellar tendon reconstruction the tendon defect has to be closed. In 50 consecutive ACL patellar tendon reconstructions, the tendon defect was randomly closed (group I) or left open (group II). The following data were recorded from all patients on the 4th and 14th days post operation: range of motion (ROM), pain at rest, pain and validity at isometric contraction, ability of bent leg raising (at 4th day) and straight leg raising (at 14th day). All the patients underwent ultrasonographic examination after 3 months and X-ray scanning at 6 months post operation. Forty patients underwent a CT-scan examination at 6 months. Thirty patients underwent isokinetic testing between 10 and 12 months post operation. Evaluating the immediate post operation data, no statistically significant differences emerged between the two groups. Ultrasonography showed in 68% of the knees of group I (defect closed) a thickened patellar tendon (PT), while in 60% of group II it was of normal thickness. No patients of either group developed patella infera by X-ray evaluation 6 months post operation. CT scans at 6 months showed that 100% of the knees of group I had a thickened PT in toto (nearly twice as thick as normal). Scar tissue was present not only in its central third but also in more than half of the cases in the medial and lateral third. In group II 75% of the patients had a normal thickness PT and 25% presented with only a minimal thickening. Scar tissue was distinguished only at its central third.(ABSTRACT TRUNCATED AT 250 WORDS)

Timing of surgery in anterior cruciate ligament-injured knees

Despite recent advances in the surgical techniques of anterior cruciate ligament (ACL) reconstruction in the past two decades, there is no consensus of opinion as to the ideal timing for ACL surgery. Based on the evolution of management of patients with ACL injuries over the period 1982-1994, we have found that various factors need to be considered in order to provide the best possible long-term result to the patient with minimal or no complications. In this review, we discuss the perioperative factors that one must consider to determine optimum timing for ACL surgery. Factors such as mental preparation of the patient; school, work, family, and social schedules; preoperative condition of the knee [i.e., minimal or no swelling, good strength, good leg control, and full range of motion (ROM) including full hyperextension]; and associated ligamentous and/or meniscal injuries must be considered before undertaking ACL surgery. With careful consideration of the above-mentioned factors and with our preoperative and postoperative rehabilitation program, we have been able to obtain predictable, successful, long-term results following ACL reconstruction in our athletic population. We emphasize that every patient should be treated on his or her own merit, and treatment decisions must be individualized.

Prevention of arthrofibrosis after anterior cruciate ligament reconstruction using the central third patellar tendon autograft

A retrospective analysis was performed to explain the decreasing incidence of postoperative arthrofibrosis of the knee in 191 consecutive patients who had anterior cruciate ligament reconstruction using the central third patellar tendon from 1987 through 1991. Follow-up data were available on 188 patients (98%). Age, sex, time interval from injury, preoperative motion, and concomitant meniscal repair or partial meniscectomy were evaluated for their significance as risk factors. Twenty-two of 188 patients (12%) developed arthrofibrosis; the incidence was lower when the acute anterior cruciate ligament reconstruction was delayed at least 3 weeks from the injury, and when preoperative extension was 10 degrees or better. Age, sex, preoperative flexion, and need for concomitant meniscal surgery were not risk factors. The postoperative motion protocol evolved during the study period. Group 1 patients were braced in 45 degrees of flexion for 1 week before passive extension was allowed. In Group 2, motion was started after 48 hours. Group 3 patients were braced in full extension, with motion starting with 24 hours. With these changes, the incidence dropped from 23% to 3%. Decreases in the incidence of arthrofibrosis with modifications in operative technique and postoperative analgesia were not statistically significant.

Healing of the patellar tendon after harvesting of its mid-third for anterior cruciate ligament reconstruction and evolution of the unclosed donor site defect

The purpose of this study was (a) to evaluate by ultrasonography the healing of the patellar tendon after its mid-third was removed for anterior cruciate ligament (ACL) reconstruction in two randomized groups of patients in whom the tendon donor site was either left open or closed; (b) to compare clinical, radiographic, and isokinetic studies of these two groups to evaluate the incidence of patellofemoral disorders. We performed 61 ACL reconstructions (22 males, 39 females) using the arthroscopically assisted in-out technique. All operations were performed by the same surgeon, and the patients were all subjected to the same postoperative protocol. The tendon defect was left open in 25 subjects (group A) and was closed in 36 subjects (group B). Postoperative patellar tendon behavior was evaluated in these two groups by ultrasonography at 3, 6, 9, and 12 months. The vertical position of the patella was measured in the follow-up lateral view at 45 degrees of flexion and compared to that of the untreated knee. A clinical evaluation was performed throughout the follow-up period, and patellofemoral problems (pain, stiffness, patello-femoral crepitus) were evaluated and recorded using a modified Larsen and Lauridsen rating scale. Isokinetic evaluation was carried out at 6 months, and a quadriceps index of the two groups was recorded. Ultrasonography showed that healing of the patellar tendon initially progressed with a compensatory hypertrophy in width and thickness. The width was greater in group B (P < 0.01). In group A we observed in the cross-sections a characteristic image of two cords separated by a low signal bridge which we defined as a "binocular pattern." Areas of high ultrasound signal intensities persisted after 1 year in the open group; such areas were filled with scar tissue. In the closed group the ultrasound tendon signal returned to normal at 1 year. At 6 months the clinical, radiographic and isokinetic findings did not significantly differ between the open and closed groups. We conclude that defect closure after patellar tendon harvesting does not significantly influence the extensor apparatus.

Post-operative problems following anterior cruciate ligament reconstruction

Seventy adult patients were studied during the postoperative rehabilitation period following anterior cruciate ligament reconstruction in order to investigate the role of pre-, intra-, and postoperative factors in range of motion and graft problems. A standard bone-patellar tendon-bone autograft was used for the reconstruction. Pre- and intraoperative factors such as concomitant injuries, time from injury to surgery, age, sex, and tunnel placement were recorded. Tunnel placement was recorded on intraoperative radiographs of the final guide pin placement and compared to pin placement on cadaver knees. The results indicated a significant relation between early reconstruction (< 1 month) following the injury and range of motion problems during the early rehabilitation period (P < 0.001). This relation disappeared by the end of the first postoperative year. Prolonged surgery was also associated with early motion problems (P < 0.05). Graft laxity or failure was correlated with an earlier return of range of motion (P < 0.05). We hypothesized that graft failure can have a biologic cause rather than a mechanical one since intraoperative X-rays indicated a near-anatomic tunnel placement in this patient group when compared to ideal placement in the cadaver knees.

Arthroscopic management of postoperative arthrofibrosis of the knee joint: indication, technique, and results

From October 1987 through March 1991, 58 patients with postoperative joint stiffness underwent arthroscopic fibroarthrolysis. Forty-six knees in 46 patients were followed. The indication for arthroscopic management was decreased range of motion after surgery. Eighty-seven percent had been treated by arthrotomy. Thirteen percent had been managed by arthroscopic surgery. The indication for primary surgery was a torn anterior cruciate ligament in 74%. The mean interval between arthroscopic fibroarthrolysis and follow-up was 22.1 months. The average age was 32.7 years. A modified Blauth and Jäger score was used for classification of fibroarthrosis: grade I (mild 17.4%), grade II (moderate 63%), grade III (severe 15.2%), and grade IV (bad 4.3%). The gain in range of motion was evaluated by the Cauchoix index: the results were excellent in 54.5%, good in 21.7%, and fair and poor in 23.8%. Pain was evaluated according to a modification of the Lysholm score: 80.4% of the patients experienced a reduction in pain. The sports activity level in the Tegner activity scale increased from 2.3 to 4.8. Patient satisfaction was excellent or good in 56.5% (n = 26), fair in 39.1% (n = 18), and poor in 4.3% (n = 2). On the basis of our retrospective study, we feel that arthroscopic fibroarthrolysis is of benefit to the patients with postoperative joint stiffness even after a prolonged period.

[Replacement of the anterior cruciate ligament by a PET prosthesis (Trevira extra-strength) as a salvage procedure in chronically unstable previously operated knee joints. Intermediate to long-term results of a clinical study]

Thirty-one salvage cases of chronically unstable previously operated knees were stabilized by an anterior cruciate ligament prosthesis of polyethyleneterephthalate (Trevira hochfest) and additional repair of concomitant lesions. The patients were followed up at yearly intervals. For the final follow-up after 4.4 years 27 patients could be evaluated clinically, radiologically and by several scores. The pre-operative Lysholm score was 59.8 (+/- 16.7). It was raised significantly by the operation to 75.4 (+/- 18.9) after 1 year, but then gradually decreased to 71.4 (+/- 19.6) at the final examination. Similar values were reached for the other scores (OAK, IKDC, VAS). The degree of activity (as estimated by the Tegner activity scale) increased from 2.0 (+/- 2.1) to 3.1 (+/- 1.9). Pre-operative anterior translation revealed a side-to-side difference of 7.5 (+/- 3.4) mm. The stability, which was restored by the operation, gave way a little in the first 2 years up to a side-to-side difference of 2.1 (+/- 2.5) mm, but then remained constant and was measured 2.3 (+/- 2.9) mm after 4.4 years. On the whole, the patients gained a significant improvement from the operation in all investigated parameters. Major complications included 5 ruptures of the synthetic ligament (1 by material fatigue), 1 avulsion of a staple, 1 supracondylar fracture due to 3 closely located staples, 4 cases of arthrofibrosis and 1 case of chronic knee irritation. The gradual deterioration of the operated knees within the follow-up period is mainly caused by the pre-existing chronic degenerative changes, which progress in spite of a sufficient stabilization of the central pivot.

Risk factors for restricted motion after anterior cruciate reconstruction

A retrospective review of 373 patients who had undergone anterior cruciate ligament (ACL) reconstruction utilizing the central third of the patellar tendon was undertaken to identify those factors that placed a patient at risk for restricted postoperative motion (flexion < or = 125 degrees or flexion contracture > or = 10 degrees). Stepwise logistic regression analysis determined that the variables most strongly correlated with restricted final range of motion (ROM) were open surgery (P = .0008) and reconstruction performed < or = 7 days after the initial injury (P = .004). Age, associated meniscal repair, or associated collateral ligament injuries did not significantly affect the ROM. A subgroup of 204 patients arthroscopically reconstructed more than 7 days post-injury were significantly less likely to have limited motion when ROM exercises were begun within 2 days of surgery (P = .008). These data support delayed, arthroscopic ACL reconstruction followed by early ROM exercises as useful techniques for avoiding postoperative motion problems.

The importance of the posterior oblique ligament in repairs of acute tears of the medial ligaments in knees with and without an associated rupture of the anterior cruciate ligament. Results of long-term follow-up

Forty-one of fifty patients (fifty knees) who had had a repair of an acute tear of the medial ligaments, a procedure in which repair of the posterior oblique ligament and the semimembranosus complex was emphasized, were re-evaluated after an average duration of follow-up of twenty-two years (range, eighteen to thirty years). The ages of the patients at the time of the injury had ranged from fifteen to twenty-one years. In twenty-four of the forty-one knees, the anterior cruciate ligament had been torn. In seventeen of these knees, the torn ligament had been debrided; in six others, which had had avulsion of a bone fragment or a terminal tear, the ligament had been repaired with absorbable sutures; and in the remaining knee, the repaired anterior cruciate ligament had been augmented. Four patients had had a pes anserinus transfer to supplement the medial repair. The medial meniscus had been intact or repaired in twenty-five of the forty-one knees and had been removed from the remaining sixteen. The lateral meniscus had been retained in thirty-nine knees and removed from two. Postoperatively, all knees had been immobilized for six weeks in 60 degrees of flexion by means of a plaster cast. This had not caused lasting loss of motion, persistent muscle atrophy, or clinically demonstrable deterioration of the articular cartilage. In the twenty-four knees that had had a tear of the anterior cruciate ligament, the rates of instability, meniscal injury, and deterioration of the joint had not increased since the time of treatment, compared with those in the knees with an intact ligament, even though repair and augmentation of this ligament had not been performed (except in one patient, in whom it was unsuccessful). Thirty-eight patients had good stability and a normal range of motion, as well as little or no muscle atrophy. Radiographic changes were slight or absent in all but four knees. Most patients had maintained a high level of physical fitness and recreational athletic activity. There were three failures of treatment (7 per cent). This previously described treatment of acute tears of the medial ligaments, with or without an associated tear of the anterior cruciate ligament, provides good long-term results and is still recommended.

Current Protocols and Procedures for Anterior Cruciate Ligament Reconstruction and Rehabilitation

In an attempt to quantify the current standards in surgical procedures and rehabilitation protocols utilized to treat patients with anterior cruciate ligament (ACL)-deficient knees, a 19-question survey was sent to members of the Hawaii Orthopedic Association. The findings indicated that only 54% (30/56) of the respondents were performing ACL reconstructions, of which 87% (26/30) were performing an intra-articular procedure and none were performing extra-articular procedures exclusively. The findings further indicate that 80% (24/30) of the 30 respondents performing ACL reconstructions were using an arthroscopically assisted, bone-tendon-bone autograft procedure. However, in marked contrast to the uniformity that existed concerning the surgical procedure, there was a drastic difference in the rehabilitation protocols and procedures that were recommended postoperatively. The most apparent differences in rehabilitation protocols existed in the utilization and initiation of open versus closed type kinetic chain exercises and activities.

Infrapatellar contracture syndrome. Diagnosis, treatment, and long-term followup

Infrapatellar contracture syndrome is an uncommon but recalcitrant cause of reduced range of motion after knee surgery or injury. The results and conclusions presented here are based on a retrospective clinical study evaluating the long-term outcome in 75 patients who developed infrapatellar contracture syndrome. These 75 patients (76 knees) were evaluated at an average followup of 53 months after the index (inciting) procedure or injury. Comparing subgroups within the study population, factors that correlated with poorer results or more severe infrapatellar contracture syndrome were found to be acute anterior cruciate ligament repair or reconstruction, the use of patellar tendon autograft for anterior cruciate ligament reconstruction, nonisometric graft placement, multiple surgical procedures, use of closed manipulation, and the development of patella infera. We concluded that appropriate procedures can substantially increase the range of motion in patients with infrapatellar contracture syndrome. However, residual functional morbidity persists in many patients, and the outcome, as determined by subjective knee function scores, is only fair. The natural history of an anterior cruciate ligament-deficient knee appears to be more benign than the natural history of a knee that develops infrapatellar contracture syndrome.

Isolated autogenous bone-patellar tendon-bone graft site morbidity

To distinguish between morbidity caused by the isolated patellar tendon graft harvest and morbidity associated with anterior cruciate ligament reconstruction when the graft is harvested from the involved knee, we studied 20 patients who had an isolated contralateral graft harvest for anterior cruciate ligament reconstruction in the opposite knee. We defined and quantitated the morbidity by evaluating the uninjured knee from preoperative studies to current followup (range, 0.5 to 5 years; average, 2 years). All graft harvest surgeries were performed in an identical fashion. Rehabilitation of the harvest knee included immediate range of motion, weightbearing, and closed chain kinetic exercises with a emphasis on early strengthening. All patients regained full knee range of motion by 3 weeks. At final followup, there was no clinical or radiographic evidence of patella contracture or baja. Quadriceps strength averaged 69% at 6 weeks and returned to 93% at 1 year and 95% at 2 years. Activity-related soreness at the donor site (patellar tendinitis) was rarely restricting and resolved after the 1st year. No patient complained of patellofemoral joint pain in the donor knee. The modified Noyes subjective questionnaire score averaged 97 of 100 at last followup. The morbidity of an isolated autogenous patellar tendon graft harvest appears to be of short duration and largely reversible.

Graft impingement after anterior cruciate ligament reconstruction. Presentation as an active extension "thunk"

Twelve of 215 patients with an anterior cruciate ligament reconstruction developed a "thunk," a low-pitched sound, on active extension of the operative knee at an average of 5 months after surgery. In 4 of the patients the thunk resolved without surgical treatment at an average of 4 months after onset (range, 2 to 6). In 3 of the patients an increase in anterior knee laxity was associated with resolution of the thunk. Seven of the patients were treated with arthroscopic examination. Six of the patients had graft impingement on the lateral wall or the roof of the notch with knee extension. The thunk was eliminated with an adequate notchplasty that corrected the impingement. In the other patient the thunk was secondary to fibrosis of the anterior fat pad. One patient with a persistent thunk declined surgery and was lost to followup.

Outpatient surgical management of arthrofibrosis after anterior cruciate ligament surgery

We present a consecutive series of nine patients who were referred to us because of arthrofibrosis (loss of > 15 degrees of extension) after intraarticular anterior cruciate ligament reconstruction using autogenous patellar tendon (eight patients) or semitendinosus (one patient) graft. Eight patients had surgery within 2 weeks of injury. All patients had been immobilized in flexion after the anterior cruciate ligament reconstruction and they had failed to improve despite vigorous physical therapy and other closed methods of treatment. The mean time from anterior cruciate ligament reconstruction to the subsequent surgery was 10.2 months (range, 3 to 14). The patients underwent an outpatient arthroscopic anterior scar resection, notchplasty, a closed knee manipulation for flexion, and extension casting. Serial daily extension cast changes allowed the patients to obtain full extension, which was maintained by a bivalved extension splint for bedtime use. Flexion was actively sought by aggressive outpatient physical therapy. All patients except one noted near-normal ultimate range of motion. One patient could only attain 10 degrees short of flat extension at the end of his rehabilitation and was considered a failed result. At final followup (mean, 31 months), no patient complained of symptoms of instability, all had a normal gait, and all but one were able to return to athletic activities.

The surgical treatment of arthrofibrosis of the knee

Sixty-one lysis of adhesion procedures were performed for arthrofibrosis of the knee between 1981 and 1990. In 43 cases (37 patients) the etiology was prior knee ligament surgery. Ten cases had sustained fractures about the knee and eight had miscellaneous etiologies. Six patients required a second lysis of adhesion procedure. A retrospective analysis of the 43 ligament patients was undertaken to evaluate the results of surgical treatment. All 43 cases were available for followup at an average of 3.6 years. Surgical indications included flexion or extension deficits of > or = 10 degrees or when motion failed to improve despite 2 months of intense therapy. Follow-up assessment included clinical and radiographic evaluation. Flexion improved from 83% to 97% of the contralateral side. Extension deficits improved from 14 degrees to 3 degrees. Only 23 of 37 patients (62%) achieved satisfactory functional results. Radiographic evidence of degenerative changes, soft tissue calcification, and patella infera was found in 89%, 51%, and 9% of the patients, respectively. Patients requiring surgical treatment for arthrofibrosis after knee ligament surgery achieved excellent motion gains, but functional outcome scores were compromised and radiographic findings were concerning. Patients with the localized anterior intraarticular variant or those undergoing lysis of adhesion surgery sooner than 6 months had outcomes comparable with controls.

Pain after use of the central third of the patellar tendon for cruciate ligament reconstruction. 33 patients followed 2-3 years

We performed reconstruction of the anterior cruciate ligament in 33 patients using the central third of the patellar tendon. In 20 patients we did an arthroscopically-assisted procedure, while 13 patients had an additional mini-arthrotomy through the gap in the patellar tendon. After 2-3 years the subjective knee function, according to the Lysholm score, was excellent or good in 18 knees and fair or poor in 15 knees, mainly due to anterior knee pain. Although 18 patients complained about anterior knee pain, only 1 patient required further surgery. After the operation the patella had a lower position. A flexion contracture was found in 7 patients, and 13 had heterotopic bone formation at the apex of the patella. Although stability was restored in 31 of the 33 reconstructed knees, anterior knee pain was a frequent complication. There were no correlations between the anterior knee pain and patellar height, flexion contracture or heterotopic bone formation.

Early development of patella infera after knee fractures

The condition referred to as patella infera is characterized by a permanent shortening of the patellar ligament and is associated with a severely limited range of motion of the knee joint. Patella infera is a common complication of injury or surgery to the knee joint, and it is generally considered a condition that presents after a variable, albeit considerable time after injury. A review of the knee roentgenograms of patients with arthrofibrosis and patella infera showed this condition to be an immediate complication of knee fractures. Therefore, in order to better define the development of patella infera, the patellar height was studied during treatment of 146 knee joint fractures (46 supracondylar fractures, 50 patellar fractures and 50 tibial plateau fractures). Using the Caton-Deschamps method patella infera was detected in eight cases (17.39%) immediately after supracondylar fractures, in six cases (12%) after patellar fractures, and only in two cases (4%) after tibial plateau fractures. The patellar ratio remained unchanged or worsened further after treatment, and its incidence was unaffected by the type of treatment. These observations rule out etiologies such as inflammatory or algodystrophic phenomena and quadriceps inhibition, because the reduction of patellar height was evident immediately and persisted at follow-up examinations.