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

Right-Left Differences in Knee Extension Stiffness for the Normal Rat Knee: In Vitro Measurements Using a New Testing Apparatus

Knee stiffness following joint injury or immobilization is a common clinical problem, and the rat has been used as a model for studies related to joint stiffness and limitation of motion. Knee stiffness measurements have been reported for the anesthetized rat, but it is difficult to separate the contributions of muscular and ligamentous restraints to the recorded values. in vitro testing of isolated rat knees devoid of musculature allows measurement of joint structural properties alone. In order to measure the effects of therapeutic or surgical interventions designed to alter joint stiffness, the opposite extremity is often used as a control. However, right-left stiffness differences for the normal rat knee have not been reported in the literature. If stiffness changes observed for a treatment group are within the normal right-left variation, validity of the results could be questioned. The objectives of this study were to utilize a new testing apparatus to measure right-left stiffness differences during knee extension in a population of normal rat knees and to document repeatability of the stiffness measurements on successive testing days. Moment versus rotation curves were recorded for 15 right-left pairs of normal rat knees on three consecutive days, with overnight specimen storage in a refrigerator. Each knee was subjected to ten loading-unloading cycles, with the last loading curve used for analysis. Angular rotation (AR), defined here as the change in flexion-extension angle from a specified applied joint moment, is commonly used as a measure of overall joint stiffness. For these tests, ARs were measured from the recorded test curves with a maximum applied extension moment of 100 g cm. Mean rotations for testing days 2 and 3 were 0.81-1.25 deg lower (p < 0.001) than for day 1, but were not significantly different from each other. For each testing day, mean rotations for right knees were 1.12-1.30 deg greater (p < 0.001) than left knees. These right-left stiffness differences should be considered when interpreting the results of knee treatment studies designed to alter knee stiffness when using the opposite extremity as a control.

Rehabilitation Following Meniscal Root Repair: A Clinical Commentary

There is a growing body of evidence surrounding the pathology and treatment of meniscal root tears. As surgical techniques are being developed and refined, rehabilitation protocols for meniscal root repairs must be defined and tested. Little information has been published regarding specific rehabilitation parameters for meniscal root repairs through all phases of rehabilitation. The goal of this commentary is to describe a rehabilitation program for meniscal root repairs that is founded on anatomical, physiological, and biomechanical principles with criteria-based progressions.

Fibrosis is a common outcome following total knee arthroplasty

Total knee arthroplasty (TKA) is one of the most successful orthopaedic procedures that alleviates pain and restores function in patients with degenerative knee joint diseases. Arthrofibrosis, abnormal scarring in which dense fibrous tissue prevents normal range of motion, develops in ~3–10% of TKA patients. No prophylactic intervention is available and treatment is restricted to aggressive physiotherapy or revision surgery. Tissue was collected from patients undergoing primary (n = 30) or revision (n = 27) TKA. Revision patients were stratified as non-arthrofibrotic and arthrofibrotic. Tissue was macroscopically and histologically compared to improve our understanding of the pathophysiology of arthrofibrosis. Macroscopically, tissue from primary TKA presents as homogenous, fatty tissue whereas tissue from revision TKA presents as dense, pigmented tissue. Histologically, there was dramatic tissue remodelling, increased collagen deposition and increased (myo)fibroblast staining in tissue from revision TKA. Significantly, tissue architecture was similar between revision patients regardless of clinically diagnosis. There are significant differences in architecture and composition of tissue from revision TKA over primary TKA. Surprisingly, whether revision TKA were clinically diagnosed as arthrofibrotic or non-arthrofibrotic there were still significant differences in fibrotic markers compared to primary TKA suggesting an ongoing fibrotic process in all revision knees.

A potential mode of action for Anakinra in patients with arthrofibrosis following total knee arthroplasty

Arthrofibrosis is a fibroproliferative disease characterised by excessive deposition of extracellular matrix components intra-articularly leading to pain and restricted range of movement. Although frequently observed following total knee arthroplasty (TKA) no therapeutic options exist. A pilot study demonstrated that intra-articular injection of Anakinra, an IL-1R antagonist, improved range of movement and pain in patients with arthrofibrosis however the mechanism of action is unknown. We hypothesise that IL-1α/β will drive an inflammatory phenotype in fibroblasts isolated from the knee, therefore identifying a potential mechanism of action for Anakinra in arthrofibrosis following TKA. Fibroblasts isolated from synovial membranes and infra-patellar fat pad of patients undergoing TKA express high levels of IL-1R1. Stimulation with IL-1α/β induced a pro-inflammatory phenotype characterised by increased secretion of GMCSF, IL-6 and IL-8. No significant difference in the inflammatory response was observed between fibroblasts isolated from synovial membrane or infra-patellar fat pad. IL-1α/β treatments induced a pro-inflammatory phenotype in fibroblasts from both synovial membrane and infra-patellar fat pad and therefore Anakinra can likely have an inhibitory effect on fibroblasts present in both tissues in vivo. It is also likely that fibroblast responses in the tissues are controlled by IL-1α/β availability and not their ability to respond to it.

A conceptual framework for a sports knee injury performance profile (SKIPP) and return to activity criteria (RTAC)

Injuries to the knee, including intra-articular fractures, ligamentous ruptures, and meniscal and articular cartilage lesions, are commonplace within sports. Despite advancements in surgical techniques and enhanced rehabilitation, athletes returning to cutting, pivoting, and jumping sports after a knee injury are at greater risk of sustaining a second injury. The clinical utility of objective criteria presents a decision-making challenge to ensure athletes are fully rehabilitated and safe to return to sport. A system centered on specific indicators that can be used to develop a comprehensive profile to monitor rehabilitation progression and to establish return to activity criteria is recommended to clear athletes to begin a progressive and systematic approach to activities and sports. Integration of a sports knee injury performance profile with return to activity criteria can guide clinicians in facilitating an athlete's safe return to sport, prevention of subsequent injury, and life-long knee joint health.

Efficacy of passive extension mobilization in addition to exercise in the osteoarthritic knee: an observational parallel-group study

STUDY DESIGN

Pretest post-test observational parallel-group design.

OBJECTIVES

To evaluate the efficacy of passive knee extension mobilization in addition to exercise therapy on extension range of motion (ROM) in patients with osteoarthritis (OA) of the knee. Secondary objectives were to determine changes in pain and functional abilities.

BACKGROUND

Patients with knee OA complain of pain, limited range of motion, and impaired activities. Efficacy of mobilization as a treatment option next to exercises has not been studied rigorously.

METHODS AND MEASURES

Thirty-four participants with persistent knee pain, a positive radiography for knee OA, and a passive extension deficit were included. Seventeen participants (mean age±SD, 59.8±6.1years) were treated with an exercise protocol and were additionally given manual mobilizations to improve passive extension ROM. The other group (mean age±SD, 61.5±7.3years) with equal characteristics was treated with an identical exercise therapy protocol only. Prior to participation, detailed ROM measurements were recorded next to muscle function tests, pain (VAS), six-minute walking tests (6MWTs), a condition-specific questionnaire, and the patient-specific function scale (PSFS). Participants in both groups completed 16 treatment sessions each.

RESULTS

Passive mobilization significantly improved extension ROM in the intervention group (5.2 versus 8.6°, p=.017). The manually mobilized group also had better physical capacities as assessed by 6MWT, less pain, and a lower PSFS score.

CONCLUSION

A combined protocol including exercise therapy and passive mobilization was beneficial for patients with OA of the knee complaining of pain, decreased extension ROM and decreased limited abilities.

LEVEL OF EVIDENCE

Therapy, 2b.

Treatment of patella infera by patellar tendon lengthening and augmentation with tibialis anterior tendon allograft

Management of patella infera remains a difficult therapeutic endeavor. We report a case of a 21-year-old man, who had development of patella infera and knee flexion contracture after a patella fracture. Patella infera was treated by patellar tendon lengthening and augmentation with a tibialis anterior tendon allograft fixed with bioabsorbable cross-pins. The patient regained an anatomic patellar position and full range of motion at two years after surgery.

Prognostic factors of arthroscopic adhesiolysis for arthrofibrosis of the knee

Purpose

To assess the results of arthroscopic adhesiolysis for arthrofibrosis of the knee and to investigate possible prognostic factors.

Materials and Methods

Among the patients who developed arthrofibrosis after knee joint surgery, 68 patients who underwent arthroscopic adhesiolysis and were available for at least one-year follow-up were evaluated with regard to the Lysholm knee score, International Knee Documentation Committee (IKDC) subjective knee score, patient satisfaction, and range of motion (ROM) of the knee. The influence of possible prognostic factors including the cause of arthrofibrosis, duration of disease, and age of the patient on the postoperative ROM was analyzed.

Results

Sixty-one patients (89.7%) obtained an average increase of 48.6° in ROM; however, the remaining seven patients (10.3%) did not show any increase at the final follow-up. The Lysholm knee score and IKDC subjective knee score increased significantly at the final follow-up. Patient satisfaction was high or very high in 89.7% of the patients at the final follow-up. There was no association between the cause of arthrofibrosis and the increase in postoperative ROM. The duration of disease was significantly related to the postoperative recovery of ROM. Age had no significant influence on the postoperative recovery of ROM.

Conclusions

We believe that arthroscopic adhesiolysis is effective for the treatment of intraarticular arthrofibrosis. In particular, the duration of the disease had significant influence on the postoperative outcome.

The treatment of acquired patella baja with proximalize the tibial tuberosity

PURPOSE

Acquired patella baja may result in decreased range of motion of the knee, extensor lag, and anterior knee pain. The aim of the study was to evaluate the efficacy of tibial tubercle osteotomy with proximal displacement.

METHODS

Between 1998 and 2011, a proximalization of the tibial tuberosity was performed in 15 patients (15 knees) with patella baja diagnosed using the Blackburne-Peel ratio. Clinical outcomes included the Tegner Lysholm knee scoring scales, the WOMAC questionnaire, the short form-12 (SF-12), and a visual analogue score (VAS) pain scale.

RESULTS

Fifteen proximalizations of the tibial tuberosity were performed, with a mean follow-up period of 64 months (5-160). The mean patient age was 59 years (41-86 years). The mean preoperative Blackburne-Peel ratio of 0.4 (0.1-0.6) was improved to a mean of 1.0 (0.8-1.2) post-operatively, which was associated with significant improvements in the Lysholm knee scoring scale from 13.3 ± 13.0 to 86.7 ± 10.4 points (p < 0.0001). Quality of life, as measured using the SF-12 outcome, also improved significantly (p < 0.0001), as did all WOMAC questionnaire score subscales (p < 0.0001). The VAS preoperative status for pain improved from 8.3 ± 2.0 to 1.5 ± 1.8. No patient had delayed or non-union of the osteotomy site.

CONCLUSIONS

A series of patients with patella baja, treated with proximalization of the tibial tuberosity, achieved satisfactory outcomes in terms of pain relief and improved function, without major complication.

Does infrapatellar fat pad resection in total knee arthroplasty impair clinical outcome? A systematic review

INTRODUCTION

The infrapatellar fat pad (IPFP) is often removed during total knee arthroplasty (TKA). No evidence based guidelines on changes in clinical outcome have yet been described. The aim of this review is to investigate whether regular removal of the IPFP during TKA should be performed.

MATERIAL AND METHODS

Seven databases were systematically searched. Clinical studies, in which TKA with IPFP resection was compared with IPFP preservation, were included. Risk of bias was assessed using the Cochrane collaboration tool. Studies reporting anterior knee pain, patellar tendon length, range of motion, patellar vascularisation or functional outcome were included.

RESULTS

The indication for TKA varied in the different studies: osteoarthritis (OA), rheumatic arthritis (RA) and multiple indications (OA, RA and osteonecrosis). After IPFP resection: 1. For OA, no differences in function, range of motion, and anterior knee pain were found. 2. In the RA study, there was a trend towards more discomfort and a decrease in function. 3. In OA and RA patients a decrease in patellar tendon length was observed. 4. One study reported no decrease in patellar vascularisation.

DISCUSSION

Limitations of this review are the high risk of bias scores of the included studies, the varying outcome measures, follow up, number and type of participants. Randomised clinical trials are required to support or refute the results, contributing to a possible future evidence based guideline on IPFP resection during TKA.

Adhesive capsulitis of the knee

The authors describe the case of a 42-year-old woman presenting with significant knee pain and disability. Her imaging findings using contrast MR imaging and FDG PET/CT suggested adhesive capsulitis, which was confirmed by arthroscopy, histology, and the clinical outcome.

Perioperative rehabilitation using a knee extension device and arthroscopic debridement in the treatment of arthrofibrosis

BACKGROUND

Arthrofibrosis is a postoperative complication of intra-articular knee surgery that can be difficult to treat. Evidence suggests that maximizing knee range of motion may improve outcomes in patients with arthrofibrosis who undergo arthroscopic debridement.

HYPOTHESIS

Patients who achieve greater knee range of motion will have better subjective scores.

STUDY DESIGN

Retrospective case series analysis.

METHODS

A review of records was performed for 33 patients with arthrofibrosis who underwent knee arthroscopy and scar resection coupled with perioperative rehabilitation to maximize knee range of motion. Patient demographics and preoperative and postoperative range of motion measurements were extracted from the records. The International Knee Documentation Committee (IKDC) Subjective Knee Form was administered to assess pain, activity, and knee function. Patients performed a preoperative and postoperative rehabilitation program utilizing a knee extension device to maximize knee extension.

RESULTS

According to the IKDC range of motion criteria, 27 of 33 patients achieved normal knee extension, and 14 of 33 achieved normal knee flexion at a mean of 8.6 months after surgery. Patients with normal knee motion had a mean IKDC Subjective Knee Form score of 72.6 ± 13.6, which was significantly higher than patients who did not achieve normal motion (P = .04). Overall, mean IKDC Subjective Knee Form scores improved from 45.3 ± 16.7 preoperatively to 67.1 ± 18.0 postoperatively (P < .01) at a mean of 14.7 months after surgery.

CONCLUSIONS

Perioperative rehabilitation that emphasizes restoration of normal knee range of motion appears to improve outcomes in patients with arthrofibrosis who undergo arthroscopic scar resection. In support of our hypothesis, patients who achieved greater knee range of motion had better subjective knee scores.

Revision anterior cruciate ligament reconstruction: an update

With the rising number of anterior cruciate ligament (ACL) reconstructions performed, revision ACL reconstruction is increasingly common nowadays. A broad variety of primary and revision ACL reconstruction techniques have been described in the literature. Recurrent instability after primary ACL surgery is often due to non-anatomical ACL graft reconstruction and altered biomechanics. Anatomical reconstruction must be the primary goal of this challenging revision procedure. Recently, revision ACL reconstruction has been described using double bundle hamstring graft. Successful revision ACL reconstruction requires an exact understanding of the causes of failure and technical or diagnostic errors. The purpose of this article is to review the causes of failure, preoperative evaluation, graft selection and types of fixation, tunnel placement, various types of surgical techniques and clinical outcome of revision ACL reconstruction.

Recent advances in the rehabilitation of anterior cruciate ligament injuries

Rehabilitation following anterior cruciate ligament surgery continues to change, with the current emphasis being on immediate weight bearing and range of motion, and progressive muscular strengthening, proprioception, dynamic stability, and neuromuscular control drills. The rehabilitation program should be based on scientific and clinical research and focus on specific drills and exercises designed to return the patient to the desired functional goals. The goal is to return the patient's knee to homeostasis and the patient to his or her sport or activity as safely as possible. Unique rehabilitation techniques and special considerations for the female athlete will also be discussed. The purpose of this article is to provide the reader with a thorough scientific basis for anterior cruciate ligament rehabilitation based on graft selection, patient population, and concomitant injuries.

Current concepts for rehabilitation and return to sport after knee articular cartilage repair in the athlete

Articular cartilage injury is observed with increasing frequency in both elite and amateur athletes and results from the significant acute and chronic joint stress associated with impact sports. Left untreated, articular cartilage defects can lead to chronic joint degeneration and athletic and functional disability. Treatment of articular cartilage defects in the athletic population presents a therapeutic challenge due to the high mechanical demands of athletic activity. Several articular cartilage repair techniques have been shown to successfully restore articular cartilage surfaces and allow athletes to return to high-impact sports. Postoperative rehabilitation is a critical component of the treatment process for athletic articular cartilage injury and should take into consideration the biology of the cartilage repair technique, cartilage defect characteristics, and each athlete's sport-specific demands to optimize functional outcome. Systematic, stepwise rehabilitation with criteria-based progression is recommended for an individualized rehabilitation of each athlete not only to achieve initial return to sport at the preinjury level but also to continue sports participation and reduce risk for reinjury or joint degeneration under the high mechanical demands of athletic activity.

Arthrofibrosis after anterior cruciate ligament reconstruction in children and adolescents

INTRODUCTION

Arthrofibrosis is a known complication after anterior cruciate ligament (ACL) reconstruction. ACL reconstruction is being performed with increased frequency in the pediatric population. The purpose of this study was to determine the prevalence of arthrofibrosis in children and adolescents and to identify risk factors for arthrofibrosis.

METHODS

The study design was a retrospective case series. Medical records for 1016 consecutive ACL reconstructions in patients aged 7 to 18 years old between 1995 to 2008 at a major tertiary care children's hospital were reviewed to identify cases of postoperative arthrofibrosis. Arthrofibrosis was defined as a loss of 5 degrees or more extension compared with the contralateral knee that required a follow-up procedure or a loss of 15 degrees or more flexion compared with the contralateral knee that required a follow-up procedure. Patient data were recorded and analyzed using bivariate models to identify predictors for arthrofibrosis. Further, we reviewed the clinical course of patients with treated arthrofibrosis to assess functional outcomes of this complication.

RESULTS

Nine hundred two patients with 933 knees met the inclusion criteria for this study, of which 60% were female. The mean age at the time of surgery was 15 years (range, 7 to 18 y), and the average follow-up from original ACL reconstruction was 6.3 years (range, 1.6 to 14.2 y). The overall prevalence of arthrofibrosis in our cohort was 8.3%, with 77 of the 933 knees had at least 1 procedure to treat arthrofibrosis after ACL reconstruction. Risk factors for arthrofibrosis were female sex (11.1% females, P = 0.0001), patients aged 16 to 18 years [11.6%; odds ratio (OR) 3.51; P = 0 .007], patellar tendon autograft (OR, 1.7; P = 0.026), and concomitant meniscal repair (OR, 2.08; P = 0.007). Prior knee surgery and ACL reconstruction within 1 month of injury were not significantly associated with arthrofibrosis after ACL reconstruction. Fifty-three patients had a minimum of 6 months clinical follow-up after the procedure for arthrofibrosis. Of these, 46 patients (86.8%) had full range of motion at follow-up. Thirty-two patients (60.4%) were asymptomatic at final follow-up. Eleven patients (20.8%) complained of some persistent pain.

CONCLUSIONS

The rate of arthrofibrosis after ACL reconstruction in children and adolescents is 8.3%. Risk factors for arthrofibrosis are female sex, older adolescents, concurrent meniscal repair, and reconstruction with patellar tendon autograft. Surgical treatment for arthrofibrosis after ACL reconstruction in pediatric patients can satisfactorily regain motion in the reconstructed knee; however functional outcome may be compromised.

LEVEL OF EVIDENCE

Level 4.

Arthroscopic releases for arthrofibrosis of the knee

Intra-articular inflammation or fibrosis may lead to decreased soft-tissue and capsular compliance, which may result in pain or loss of motion within the knee. Etiology of intra-articular fibrosis may include isolated anterior interval scarring and posterior capsular contracture, as well as fibrosis that involves the suprapatellar pouch or arthrofibrosis that involves the entire synovial space. Initial nonsurgical management, including compression, elevation, and physical therapy, can decrease knee pain and inflammation and maintain range of motion. Surgical management is indicated in the patient who fails conservative treatment. Surgical options include arthroscopic releases of the anterior interval, posterior capsule, and peripatellar and suprapatellar regions. Recent advances in arthroscopic technique have led to improved outcomes in patients with intra-articular fibrosis of the knee.

Outcome of surgical treatment of arthrofibrosis following ligament reconstruction

PURPOSE

Clinical outcome following surgical treatment and intensive physiotherapy was evaluated in patients with arthrofibrosis as a complication to varying knee-ligament reconstructions.

METHODS

From 2003 to 2007, 31 patients underwent surgery for arthrofibrosis as a postoperative complication following knee-ligament reconstruction. Treatment for reduced range of motion consisted of forced manipulation or arthroscopic arthrolysis followed by intensive physiotherapy. Twenty-seven patients (12 men and 15 women; median age 35(12-70) years) were followed up. Objective examination, Pain, KOOS and Tegner scores were used to evaluate the clinical outcome at follow-up.

RESULTS

Fourteen patients were treated with forced manipulation alone, and the remaining thirteen were treated with forced manipulation and arthroscopic arthrolysis. The patients' median follow-up was 51 months (19-73 months). Median interval between primary surgery and surgical release was 4 (1-32) months. Median range of motion (ROM) improved from -0°(0 to 20) to 0°(+2-9) in extension deficit and from 90°(40-145) to 130°(90-155) in flexion. Mean KOOS score were symptoms 63, pain 72, ADL 77, sport 42, QOL 45. Median Tegner score was 4 (2-9).

CONCLUSION

Surgical arthrolysis combined with intensive physiotherapy improved range of motion to nearly normal values. Subjective outcome scores revealed relatively poor outcome levels compared to uncomplicated knee-ligament reconstruction. Predictors of poor outcome were global arthrofibrosis and greater than 6-month time interval from primary reconstruction and surgical release.

LEVEL OF EVIDENCE

Retrospective clinical case series, Level IV.

Reconstruction of a patellar tendon with Achilles tendon allograft for severe patellar infera--a case report

Severe patellar infera accompanied by pathologic shortening and fibrosis of the patellar tendon is relatively an uncommmon condition but can cause recalcitrant joint stiffness and limited range of motion after knee surgery or injury. This report presents a case of a 49-year-old male with severe patellar infera and limping due to joint stiffness after three-time knee surgeries. We report a successful outcome along with a finding of the well-healed allograft after the reconstruction of a patellar tendon using Achilles tendon-bone allograft.

Effects of patellar position and defect healing on in vitro stifle joint kinematics following removal of the central one-third of the patellar tendon in an ovine model

Harvest of the central one-third of the patella tendon (PT) is routinely performed for anterior cruciate ligament reconstruction (ACLR). Patella infera may ensue. In this study we unilaterally resected the central one-third of the PT in 20 sheep, without reconstructing or defunctionalizing the native ACL, and examined the effects at 3, 6, 12, and 24 weeks postoperatively on PT length, histological appearance of the donor defect and in vitro stifle joint kinematics. Mean length increases (p > 0.263) in the operated tendons of 0.3%, 2.8%, 0.5%, and 2.4% were observed at 3, 6, 12, and 24 weeks. A significant proximal shift of the patella correlated well with a mean 2.35° retardation of patellar flexion (r = 0.440, p = 0.001). A mean net 4.9° decrease in medial patellar tilt was also observed (p < 0.001), but was not coupled with changes in tibial rotation. Donor defect tissue showed a distinct progression of healing with time, remodeling from dense scar tissue at 3 weeks to bundles of well-organized collagen enveloped by vascularized loose connective tissue at 24 weeks but was not associated with the restoration of kinematics. These results suggest that resection of the central one-third of the PT and leaving the defect open in the ovine stifle joint may be associated with increased PT length and changes in patellar kinematics which do not recover 6 months postoperatively. The lack of patella infera may render this animal model unsuitable for the interpretation of joint kinematics following PT resection for human ACLR.

The inter-rater reliability and diagnostic accuracy of patellar mobility tests in patients with anterior knee pain

BACKGROUND

Patients with patellofemoral pain syndrome (PFPS) often have nonspecific findings on clinical examination. A tight knee and diminished patellar mobility in particular, may contribute to anterior knee pain.

METHODS

Qualifying patients with anterior knee pain of > 4 weeks were sequentially examined by 2 physicians who used the patellar mobility tests. The tests evaluated for diminished patellar translation superior-inferiorly and medial-laterally, diminished patellar tendon mobility, and absent inferior pole tilt. Each of the 4 tests was scored as 1 (diminished/absent) or 0 (nondiminished/normal), with the sum of the scores determining the patellar mobility scale. Inter-rater reliability and diagnostic accuracy were determined and analyzed. Receiver operating characteristic analysis was used to determine the capacity of the patellar mobility scale to predict PFPS.

RESULTS

98 patients participated in the study. The inter-rater reliability for the 4 individual patellar mobility tests was moderately strong, with diminished medial-lateral patellar mobility demonstrating the strongest reliability (Kappa value [K], 0.59; 95% confidence interval [CI], 0.42-0.72), followed by diminished superior-inferior mobility (K), 0.55; 95% CI, -0.37 to 0.69), inferior pole tilt (K, 0.48; 95% CI, -0.28 to 0.61), and patellar tendon mobility (K, 0.45; 95% CI, -0.27 to 0.56). The diagnostic accuracy of the individual patellar mobility tests in diagnosing PFPS was fair to moderate, with the individual diminished patella tendon mobility test having the highest level of diagnostic accuracy (sensitivity, 49%; specificity, 83%; likelihood ratio [LR] ± 2.8; 95% CI, 1.3-7.3) and also having the highest positive predictive value (0.88). Diminished medial-lateral mobility was second in diagnostic accuracy (sensitivity, 54%; specificity, 69%; LR ± 1.8; 95% CI, 0.9-3.6). Receiver operating characteristic analysis showed only moderate levels of diagnostic capacity (area under the curve, 0.65) because combining all 4 patellar mobility tests to form the patellar mobility scale did not improve the diagnostic accuracy.

CONCLUSION

The clinical importance of diminished patellar and/or patellar tendon mobility findings in the evaluation of patients with anterior knee pain remains unclear. We determined that individual patellar mobility tests had moderate levels of inter-rater reliability, the best agreement found with medial-lateral mobility. The accuracy of the patellar mobility scale for diagnosing PFPS was marginal. As a tool, this cluster of examination techniques may be used by physicians to better understand their patients' conditions and descriptively communicate their findings. However, the patellar mobility scale cannot be used alone for determining the diagnosis of PFPS, as defined in our study. Future studies aim to determine whether post-treatment symptomatic improvements correlate with an improvement on the patellar mobility scale.

Functional tissue engineering of ligament healing

Ligaments and tendons are dense connective tissues that are important in transmitting forces and facilitate joint articulation in the musculoskeletal system. Their injury frequency is high especially for those that are functional important, like the anterior cruciate ligament (ACL) and medial collateral ligament (MCL) of the knee as well as the glenohumeral ligaments and the rotator cuff tendons of the shoulder. Because the healing responses are different in these ligaments and tendons after injury, the consequences and treatments are tissue- and site-specific. In this review, we will elaborate on the injuries of the knee ligaments as well as using functional tissue engineering (FTE) approaches to improve their healing. Specifically, the ACL of knee has limited capability to heal, and results of non-surgical management of its midsubstance rupture have been poor. Consequently, surgical reconstruction of the ACL is regularly performed to gain knee stability. However, the long-term results are not satisfactory besides the numerous complications accompanied with the surgeries. With the rapid development of FTE, there is a renewed interest in revisiting ACL healing. Approaches such as using growth factors, stem cells and scaffolds have been widely investigated. In this article, the biology of normal and healing ligaments is first reviewed, followed by a discussion on the issues related to the treatment of ACL injuries. Afterwards, current promising FTE methods are presented for the treatment of ligament injuries, including the use of growth factors, gene delivery, and cell therapy with a particular emphasis on the use of ECM bioscaffolds. The challenging areas are listed in the future direction that suggests where collection of energy could be placed in order to restore the injured ligaments and tendons structurally and functionally.

Case report: Patella baja after retrograde femoral nail insertion

Patella baja is a rare condition that can result from conditions involving trauma around the knee. Risk factors are believed to include scar tissue formation in the retropatellar fat pad, extensor mechanism dysfunction, and immobilization in extension. Early recognition and aggressive treatment are critical components in minimizing long-term disability. We present a case report of a woman with a fracture of the femoral diaphysis who underwent retrograde placement of an intramedullary nail. Subsequent followup revealed development of patella baja with resultant disability. The diagnosis was made late and the treatment was ineffective. Although patella baja has been reported in trauma around the knee, causative factors include retrograde femoral nailing. We believe early recognition and institution of treatment are important.

Evaluation of knee stability with use of a robotic system

In our research center, we have developed and utilized a novel robotic/universal force-moment sensor testing system to gain quantitative data on multiple-degree-of-freedom kinematics of the knee simultaneously with data on the in situ forces in normal and repaired soft tissues. In particular, we have investigated the complex interaction of the anteromedial and posterolateral bundles of the anterior cruciate ligament as well as several key biomechanical variables in anterior cruciate ligament reconstruction, such as graft selection and femoral tunnel placement (both of which impact knee stability). For example, both the bone-patellar tendon-bone and quadrupled hamstrings tendon autografts restored anterior stability but were insufficient in gaining rotatory stability. In a follow-up study, we have shown that a more laterally placed graft was beneficial and could improve these outcomes. Such findings led to additional investigation in which the biomechanical advantages of double-bundle anterior cruciate ligament reconstruction were demonstrated. However, a more laterally placed autograft at the femoral insertion of the posterolateral bundle also worked well, especially when the knee was nearly at full extension (a position in which the anterior cruciate ligament is needed most). At present, we are moving forward by obtaining in vivo kinematics data and then repeating those kinematics exactly to obtain new data with use of the robotic/universal force-moment sensor testing system in order to gain further insight regarding the function of the anterior cruciate ligament and anterior cruciate ligament replacement grafts in vivo. In parallel, we are developing a mathematical model of the knee and validating the computational model with experimental data. The combined approach will yield new and relevant information, including the stress and strain distribution in the anterior cruciate ligament and anterior cruciate ligament grafts. This will facilitate a better understanding of the function of the anterior cruciate ligament and a scientifically based design of surgical procedures and postoperative rehabilitation protocols that will lead to better patient outcomes.

Arthroscopic release for symptomatic scarring of the anterior interval of the knee

BACKGROUND

Patients with a history of knee trauma or previous surgery may exhibit pain in the infrapatellar region that is refractory to conservative care. This may be due to subtle scarring of the anterior interval.

HYPOTHESIS

Arthroscopic release of a scarred anterior interval will lead to improvement in anterior knee pain.

STUDY DESIGN

Case series; Level of evidence, 4.

METHODS

Twenty-five consecutive patients with isolated scarring of the anterior interval, confirmed with both magnetic resonance imaging (MRI) and arthroscopic examination, were included. All 25 patients had refractory anterior knee pain that was unimproved after a minimum of 6 months of physical therapy and nonsteroidal anti-inflammatory medications and pain during knee extension. All patients had a minimum of 2 previous surgical procedures, and 11 (44%) of the patients had a previous anterior cruciate ligament (ACL) reconstruction. All 25 (100%) patients had an apparent decrease in the cranial excursion of the patella and had a positive Hoffa test result. Fourteen (56%) patients had a preoperative flexion contracture of at least 5 degrees . All patients underwent an isolated arthroscopic anterior interval release.

RESULTS

All patients were evaluated by physical examination and standardized scoring instruments with an average follow-up of 4.0 years (range, 2.0-7.2). Twenty-one patients had full range of motion of the patella in all directions and a negative Hoffa test finding at final follow-up. All 14 (100%) patients with preoperative flexion contractures (>5 degrees ) experienced a full return of extension. The average Lysholm score improved from 59 preoperatively to 81 postoperatively (P < .0001). The average International Knee Documentation Committee (IKDC) score improved from 49 to 70 (P < .001). There were no complications. Four patients (16%) had failed results and required a second surgical release. Patients with failures had significantly lower preoperative Lysholm scores (score = 40) than those who did not (score = 58) (P = .022). Three of the failures were workers' compensation cases.

CONCLUSION

Scarring of the anterior interval changes the mechanics of the anterior structures of the knee and may lead to refractory anterior knee pain. Arthroscopic anterior interval release successfully provides pain relief in this patient population.

Adolescent patellofemoral pain: implicating the medial patellofemoral ligament as the main pain generator

PURPOSE

The purpose of this study is to define the clinical presentation of adolescent patellofemoral pain.

METHODS

A review was completed of all patients with patellofemoral pain at a children's hospital sports clinic over a 3-year period.

RESULTS

One hundred and one patients (91 female) with 136 symptomatic knees were identified. Mean age was 14.4 years. Knee pain was localized to the anteromedial or anterior region of the knee in 96% of patients and was typically produced with running (94%), jumping (92%) and stair use (69%). On physical examination there was usually a non antalgic gait (99%), no patellofemoral crepitation (98%), normal lower extremity angular (84%) and rotational alignment (94%), with no foot malalignment (>97%). The medial patellofemoral ligament (MPFL) was the most palpably tender area of the knee in 98% of patients. During "lateral apprehension" testing, 89% had pain at the MPFL, but not true apprehension. A "J-sign" was present at terminal knee extension in 65%. Mean Q-angle was 18.7 degrees . Means of all radiographic measures were within normal ranges.

CONCLUSION

The prototypical patient had anterior/anteromedial knee pain of insidious onset during running and jumping. The most consistent physical findings were focal tenderness at the MPFL, positive terminal J-sign, and an elevated Q-angle. Most patients required only nonsurgical treatments, but 18% underwent surgical interventions for persistent pain.

Oral corticosteroid use for loss of flexion after primary anterior cruciate ligament reconstruction

PURPOSE

Postoperative loss of motion after anterior cruciate ligament (ACL) reconstruction can lead to suboptimal outcomes. Short-term low-dose oral corticosteroids are an option for nonsurgical management of this condition. The purpose of this study is to retrospectively review a series of patients treated with a single Medrol Dosepak (MDP) (Pfizer, New York, NY) in the early postoperative period for the treatment of loss of flexion, focusing on range of motion, objective instrumented stability measurements, and complications.

METHODS

From September 1, 2003, through January 1, 2007, 28 (11%) of 252 patients who underwent primary ACL reconstruction were treated with an MDP at a mean of 6.1 weeks postoperatively (range, 4 to 12 weeks; SD, 1.4 weeks) for early postoperative loss of motion. Of these 28 patients, 4 were not included because of unavailable clinical records. One patient who underwent combined ACL and posterior cruciate ligament reconstruction with medial collateral ligament repair was excluded from the analysis. Range-of-motion and KT-1000 (MEDmetric, San Diego, CA) measurements were independently recorded by a single examiner preoperatively, at 6 weeks postoperatively, and again at final follow-up evaluation at a mean of 10.4 months (range, 4 to 24 months; SD, 4.3 months).

RESULTS

The mean flexion deficit compared with the normal, contralateral knee at the time of treatment with an MDP was 31.3 degrees (range, -2 degrees to 55 degrees ; SD, 14.8 degrees ). Patients treated with an MDP showed a significant improvement in flexion deficit (mean, 29.2 degrees; range, 0 degrees to 60 degrees ; SD, 17.1 degrees ) after MDP treatment (P < .001). KT-1000 side-to-side differences at final examination were 2 mm or less in 22 of 23 patients (mean, 1 mm; range, 0 to 4 mm; SD, 1 mm). Of the 23 patients treated with an MDP, 5 (22%) were considered failures because they required surgical intervention for persistent loss of motion, resulting in a reoperation rate for loss of motion after primary ACL reconstruction of 2.0% (5/252). There were no documented complications of MDP treatment. Specifically, no patients treated with an MDP had a postoperative infection develop.

CONCLUSIONS

The use of oral corticosteroids, in the form of an MDP, was associated with a successful return of normal range of motion in 78% of patients with early postsurgical loss of flexion and near-normal extension after primary ACL reconstruction without any associated complications or decrease in objective instrumented stability measurements.

LEVEL OF EVIDENCE

Level IV, therapeutic case series.

Arthroscopic posteromedial capsular release for knee flexion contractures

Extension deficits of the knee can cause functional limitations in patients after knee surgery or injury. Most frequently, they are treated with manipulations, arthroscopic anterior compartment debridements, or open posterior capsular releases once nonoperative treatment fails. However, an arthroscopic posteromedial capsular release to manage flexion deficits has yet to be studied comprehensively. Arthroscopic posteromedial capsular releases of the knee can result in improved knee motion postoperatively. An arthroscopic posteromedial capsular release involves sectioning the posteromedial capsule at its meniscofemoral portion, midway between its femoral attachment and its posterior horn medial meniscus junction. A review of 15 patients who underwent this operation was performed. Passive knee extension and flexion was measured in patients in the supine position using a goniometer at preoperative evaluations, under anesthesia prior to and immediately after the posteromedial capsular release, and at postoperative follow-up evaluations. The average time from the arthroscopic posteromedial capsular release to the final postoperative follow-up was 24.1 months. Preoperative knee extension averaged 14.7 degrees in 15 patients. The average immediate postoperative knee extension averaged -0.9 degrees. At the final postoperative follow-up, knee extension averaged 0.7 degrees. Overall knee motion improved from an average are of motion of 101.6 degrees-129.4 degrees. Arthroscopic posteromedial capsular releases and the concurrent postoperative rehabilitation program were effective in the treatment of knee extension deficits. The encouraging results of this study compare well to data presented in open posterior capsular release studies. We believe that arthroscopic posteromedial capsular releases are an effective means to address symptomatic knee extension deficits.

Loss of extension following anterior cruciate ligament reconstruction: analysis of incidence and etiology using IKDC criteria

PURPOSE

The purpose of this study was to determine the incidence of and factors associated with loss of extension (LOE) 4 weeks after anterior cruciate ligament (ACL) reconstruction using the new IKDC Knee Ligament Evaluation Form criteria for loss of motion.

METHODS

A retrospective review of patients who had undergone arthroscopic ACL reconstruction between 1995 and 2000 was performed. An endoscopic single tunnel technique with autograft or allograft was used in all cases. A standardized physical therapy program was prescribed to all patients. Subjects with revision ACL reconstruction, concomitant ligament surgery, meniscal transplantation, or any articular cartilage surgery were excluded. LOE was defined as greater than a 5 degrees side-to-side difference in passive knee extension 4 weeks after surgery, the need for repeat arthroscopy to restore extension, or use of a drop-out cast to restore extension.

RESULTS

Fifty-eight of 229 (25.3%) patients developed LOE 4 weeks after ACL reconstruction. LOE was not associated with age, sex, presence of nerve block, concomitant meniscal procedures, specific graft type, or tourniquet time (P > .05). LOE was significantly associated with preoperative extension, time from injury to surgery, and use of autograft (P < .05). Twenty-eight (12.2%) patients underwent an arthroscopic procedure to recover loss of motion. Following arthroscopy, 4 (1.7%) patients had passive motion deficits between 6 degrees and 10 degrees , with none greater than 10 degrees .

CONCLUSIONS

Preoperative range of motion and time to surgery are intimately related to a patient's postoperative extension. While 48% of patients that lacked full extension by 4 weeks eventually required arthroscopic debridement to achieve satisfactory extension, our treatment algorithm led to an overall incidence of LOE greater than 5 degrees at final follow-up of 1.7%.

LEVEL OF EVIDENCE

Level III, therapeutic, retrospective, comparative study.

Use of a bioscaffold to improve healing of a patellar tendon defect after graft harvest for ACL reconstruction: A study in rabbits

Following harvest of a bone-patellar tendon-bone (BPTB) autograft, the central third of the patellar tendon (PT) does not heal well. The healing tissues also form adhesions to the fat pad and can cause abnormal patellofemoral joint motion. The hypotheses were that a bioscaffold could enhance patellar tendon healing through contact guidance and chemotaxis, and the scaffold could serve as a barrier to decrease adhesion formation between the neo-PT and infrapatellar fat pad. In 20 New Zealand White rabbits, a central-third PT defect was created. One strip of porcine small intestinal submucosa (SIS) was attached to both the anterior and posterior sides of the PT defect of the SIS-treated group (n = 10). For comparison, a central defect was left nontreated (n = 10). At 12 weeks, histomorphology was examined using Masson's trichrome staining. The cross-sectional area (CSA) was determined with a laser micrometer, and the central BPTB complexes were tested in uniaxial tension. SIS-treated samples showed a greater amount of healing tissue with denser and well-oriented collagen fibers and more spindle-shaped cells. There was no noticeable adhesion formation in the SIS-treated group. For the nontreated group, there were significantly more and diffuse adhesive formations. The SIS-treated group also had a 68% increase in neo-PT CSA, 98% higher stiffness, and 113% higher ultimate load than that in the nontreated group. SIS treatment increased the quantity of healing tissue, improved the histological appearance and biomechanical properties of the neo-PT, and prevented adhesion formation between the PT and fat pad.

A mini-midvastus capsular approach with patellar displacement decreases the prevalence of patella baja

Our aim in this study was to evaluate the prevalence of patella baja after total knee arthroplasty (TKA) using 2 different surgical techniques. Postoperative changes in patella height were measured on serial radiographs of 74 TKAs implanted using a mini-midvastus capsular approach without patella eversion (group 1) and 57 TKAs implanted using a standard medial parapatellar capsular approach with patella eversion (group 2). Preoperative and postoperative Knee Society scores, operative data, and complications were compared. With a cutoff level of 5% shortening, the prevalence was 12% in group 1 and 37% in group 2 (P = .001). The presence of patella baja was related to reduced flexion and increased pain as early as 1 year after TKA.

Case series utilizing drop-out casting for the treatment of knee joint extension motion loss following anterior cruciate ligament reconstruction

STUDY DESIGN

Case series.

CASE DESCRIPTION

Four patients who had developed knee extension motion loss following anterior cruciate ligament reconstruction were referred to physical therapy for treatment. They were treated with drop-out casting and completed a Lower Extremity Functional Scale at baseline, at the time of application of the drop-out casting, and at discharge.

OUTCOMES

Three males and 1 female with a mean age of 20.5 years (range, 18-22 years) were referred to physical therapy a mean of 31 days (range, 19-49 days) following bone-patella tendon-bone autograft anterior cruciate ligament reconstruction. The mean number of physical therapy sessions attended was 29.5 visits (range, 20-47 visits). The mean improvement in knee extension range of motion (ROM) and knee flexion ROM prior to the application of drop-out casting was 4.3 degrees (range, -1 degree to 10 degrees) and 24.3 degrees (range, 0 degree to 40 degrees), respectively. The mean improvement on the Lower Extremity Functional Scale was 10.3 points prior to drop-out casting. At time of discharge, the total mean improvement in knee extension ROM loss was 11.0 degrees (range, 4 degrees to 15 degrees), knee flexion ROM was 30.8 degrees (range, 22 degrees to 35 degrees), and Lower Extremity Functional Scale was 12 points (range, -5 to 21 points). Two of the patients were able to complete a running program without difficulty, while the other 2 patients had difficulty with higher-level activities.

DISCUSSION

Despite the low incidence of knee extension ROM loss following surgery, the inability to achieve full knee extension does occur and can have debilitating consequences. When early emphasis of full passive knee extension has been inadequate, these results suggest that improving knee extension motion without inhibiting knee flexion motion is possible with the use of a drop-out cast. Future research should focus on comparison of drop-out casting to dynamic splinting, as well as the optimal frequency and duration of low-load long-duration stretching using a drop-out cast.

Patellar tendon length after knee arthroplasty with and without preservation of the infrapatellar fat pad

Our aim was to assess whether there was any significant difference in change in patellar tendon length after knee arthroplasty, when the infrapatellar fat pad was either preserved or excised. Three-year radiographic follow-up was studied on 73 primary knee arthroplasty patients. The infrapatellar fat pad was completely preserved in 38 cases and completely excised in 35. At 3 years there was a significant patellar tendon shortening of 4.2% (P = .0004) in the fat pad excision group and no significant change in the fat pad preservation group (P = .82). The difference between the 2 groups was significant (P = .004). Our results show that patella tendon length does not always shorten after knee arthroplasty and that preservation of the infrapatellar fat pad may be a factor in preventing such shortening.

Translation from Research to Applications

The article summarizes the collective views expressed at the fourth session of the workshop Tissue Engineering--the Next Generation, which was devoted to the translation of results of tissue engineering research into applications. Ernst Hunziker described the paradigm of a dual translational approach, and argued that tissue engineering should be guided by the dimensions and physiological setting of the bodily compartment to be repaired. Myron Spector discussed collagen-glycosaminoglycan (GAG) scaffolds for musculoskeletal tissue engineering. Jeanette Libera focused on the biological and clinical aspects of cartilage tissue engineering, and described a completely autologous procedure for engineering cartilage using the patient's own chondrocytes and blood serum. Arthur Gertzman reviewed the applications of allograft tissues in orthopedic surgery, and outlined the potential of allograft tissues as models for biological and medical studies. Savio Woo discussed a list of functional tissue engineering approaches designed to restore the biochemical and biomechanical properties of injured ligaments and tendons to be closer to that of the normal tissues. Specific examples of using biological scaffolds that have chemoattractants as well as growth factors with unique contact guidance properties to improve their healing process were shown. Anthony Ratcliffe discussed the translation of the results of research into products that are profitable and meet regulatory requirements. Michael Lysaght challenged the proposition that commercial and clinical failures of early tissue engineering products demonstrate a need for more focus on basic research. Arthur Coury described the evolution of tissue engineering products based on the example of Genzyme, and how various definitions of success and failure can affect perceptions and policies relative to the status and advancement of the field of tissue engineering.

Wrist arthrofibrosis

Wrist arthrofibrosis is a condition of decreased range of wrist motion due to intrinsic adhesions and extrinsic contracture. It is clinically characterized by restricted wrist range of motion, pain, swelling, and a plateau in improvement after at least 6 months of intensive physiotherapy. Other conditions must be excluded, such as articular incongruity, arthritis, spasticity, skin and subcutaneous scarring, and loose bodies. We have devised a classification system based on pathologic anatomic location, where Type I represents intrinsic adhesions, and Type II represents extrinsic contracture. The types are subdivided according to where the pathology is present. The operative approach should be wrist arthroscopy for Types IA (radiocarpal adhesions) and IB (midcarpal adhesions) where intraarticular adhesions are present. Types IC (distal radioulnar joint adhesions) and II C (distal radioulnar joint capsular contracture) are best approached in an open manner where dorsal and palmar capsulectomies of the distal radioulnar joint are performed. For Types IIA, B, and D (dorsal, palmar, and combination extrinsic contracture, respectively), both open and arthroscopic methods are described.

Anterior cruciate ligament reconstruction using hamstring tendon graft without detachment of the tibial insertion

INTRODUCTION

We report results of the anterior cruciate ligament reconstruction using a four-strand hamstring graft without detachment of the tibial insertion of the tendons.

MATERIAL AND METHODS

In 74 patients the hamstring graft was fixed using an endobutton on the femoral side and a barbed staple on the tibial side. There were 69 male and 5 female patients. The mean age at the time of operation was 35.1 years (21-53 years). Postoperatively, an accelerated rehabilitation was followed with no protective braces. The mean follow-up period was 64 months (range 48 to 84 months).

RESULTS

All patients achieved full range of motion with a stable knee joint. The mean side-to-side difference using KT-1000 was 1.43 mm (SD 3.86). The average Lysholm score improved from 42 to 79.2 and the Tegner score improved from 3.4 to 5.9.

CONCLUSION

Detachment of hamstring tendons from their tibial insertion is unnecessary and our results with accelerated rehabilitation without protective braces are satisfactory and comparable to other studies.

The effect of the Insall-Salvati ratio on outcome after total knee arthroplasty

The effect of total knee arthroplasty (TKA) on the Insall-Salvati ratio (ISR) and the effect of the ISR on the outcome of TKA have not been clearly established. A retrospective review of 1055 primary TKAs performed in 1997 to 1998 was performed. Radiographic measurements were made preoperatively and postoperatively, and the ISR was calculated. Regression analysis was performed to determine the effects of these variables on range of motion (ROM), Knee Society Score, and stair, function, and pain scores. Total knee arthroplasty resulted in a decrease in the patella tendon length, as measured by the ISR in 50% of cases. Patella infera (ISR less than 0.8) developed postoperatively in 9.8% of TKAs and was twice as likely to occur in women as men. A decrease in the ISR was associated with diminished stair and function scores (P = .0004 and 0.0081, respectively). There was no effect of the ISR upon ROM, Knee Society Score, or pain scores. Optimal outcomes occurred in patients where the ISR was not decreased after TKA, with superior stair and function scores.

A sixteen-year follow-up of three operative techniques for the treatment of acute ruptures of the anterior cruciate ligament

BACKGROUND

This study compares three surgical procedures that we used in the past to treat ruptures of the anterior cruciate ligament: acute primary repair, acute repair augmented with a synthetic ligament-augmentation device, and acute repair augmented with autologous bone-patellar tendon-bone graft.

METHODS

This is the third report on a group of patients who were randomized to the three different procedures between 1986 and 1988. There were fifty patients in each group. The patients were evaluated prospectively at one, two, five, and sixteen years with use of the Tegner activity score and the Lysholm functional score. Stability of the knee was assessed with clinical examination and with use of the KT-1000 arthrometer.

RESULTS

One hundred and twenty-nine (88%) of the 147 patients who were available for follow-up completed the study. Eleven patients (24%) who had a primary repair, four patients (10%) who had repair with a ligament augmentation device, and one patient (2%) who had augmentation with autologous bone-patellar tendon-bone graft underwent anterior cruciate ligament revisions between the primary operation and the sixteen-year follow-up examination. The rate of revision was ten times higher in the group that had primary repair than in the group that had repair with bone-patellar tendon-bone graft (p = 0.003). In the remaining patients, those who had repair with a bone-patellar tendon-bone graft had significantly more stable knees than those who had repair with a ligament augmentation device, as measured by the Lachman test (p = 0.026). Nine (11%) of the eighty-five patients for whom data were available had osteoarthritis in the primarily reconstructed knee, and three patients (3.5%) had osteoarthritis in the contralateral knee at sixteen years (p = 0.001); no difference was noted among the three groups. The mean Lysholm score at sixteen years was 88 points for the knees that had primary repair, 85 points for those that had repair with the ligament augmentation device, and 90 points for those managed with a bone-patellar tendon-bone graft (p = 0.286).

CONCLUSIONS

At long-term (sixteen-year) follow-up, the rate of revision anterior cruciate ligament surgery is much higher following primary repair than after primary repair augmented by a bone-patellar tendon-bone graft. It can be expected that approximately 10% of patients undergoing anterior cruciate ligament reconstruction acutely will have osteoarthritis develop in the reconstructed knee. We no longer perform any of these surgical techniques as open procedures.

Die Arthrolyse bei chronischen Beugedefiziten des Kniegelenks

AIM AND METHOD

Limitations to the range of motion of the knee reduce knee function and life quality. Flexion deficits inhibit using stairs and shoe closure, and may cause social deprivation. We present a pathophysiological concept of arthrolysis of the knee for flexion deficit. Our concept divides into intra- and extra-articular factors involving knee stiffness. Extra-articular problems can be located proximally in the quadriceps mechanism and distally in the patellar tendon.

RESULTS

The main proximal factor is fibrosis of the vastus intermedius muscle (MVI) which is treated by MVI-resection; the main distal factor is shortening of the patellar tendon which is treated by z-plasty of the this tendon or transposition of the tibial tuberosity. Intra-articular factors are adhesions and fat pad fibrosis. These conditions can be treated by arthroscopic or limited open arthrolysis and eventually z-plasty of the retinacula.

CONCLUSION

A strict postoperative protocol is obligatory for pain control and physiotherapy. In 19 cases treated with this algorithm there was a mean flexion gain of 26 degrees. The AOSSM subjective outcome score was excellent in ten and good in seven cases after a mean follow-up of 8.2 months. This treatment protocol allows improvement in flexion, even in difficult revision cases.

Anterior cruciate ligament revision reconstruction: results using a quadriceps tendon-patellar bone autograft

BACKGROUND

The quadriceps tendon is a viable graft source for revision anterior cruciate ligament reconstruction.

PURPOSE

To determine the functional results and graft failure rates in knees in which the patellar tendon had been previously harvested or was unavailable, expanded tunnels precluded the use of a semitendinosus-gracilis graft, or patients requested autogenous tissues instead of allografts for revision reconstruction.

STUDY DESIGN

Case series; Level of evidence, 4.

METHODS

The authors observed 21 patients for a mean of 49 months postoperatively after revision anterior cruciate ligament reconstruction with a quadriceps tendon graft. The results were determined by KT-2000 arthrometer testing, the Cincinnati Knee Rating System, and the International Knee Documentation Committee Rating System. Fifteen knees required a concurrent procedure, including reconstruction of posterolateral structures in 5 knees, meniscal repairs in 5 knees, and high tibial osteotomy in 2 knees.

RESULTS

Significant improvements occurred in symptoms (P < .0001), daily activities (P < .05), sports activities (P < .01), and the overall rating scores (P < .0001). Eighteen patients rated their knee condition as improved. Total mean anterior-posterior displacements decreased from 8.4 +/- 3.1 mm preoperatively to 2.0 +/- 2.3 mm at follow-up (P < .001). On the International Knee Documentation Committee knee ligament rating, 17 knees were graded as normal or nearly normal, 3 were graded as abnormal, and 1 was graded as severely abnormal.

CONCLUSION

The revision operation provided reasonable results in this group of complex knees. However, the functional and overall results were inferior to those reported for primary anterior cruciate ligament reconstruction. Many knees (90%) had compounding problems of articular cartilage damage, meniscectomy, varus malalignment, or additional ligamentous injury that most likely affected the results.