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PubMed2003

The anatomy and reconstruction of the medial patellofemoral ligament.

INTRODUCTION: Reconstruction of the MPFL for recurrent and acute lateral dislocation of the patella is becoming more accepted. This study aimed to further define the medial patellofemoral ligament (MPFL) anatomy and to describe the most suitable sites for graft attachment when reconstructing the MPFL. MATERIALS AND METHODS: Anatomical dissection was performed on 25 embalmed knee specimens. Four separate specimens were used to assess graft fixation points. Sites were tested for isometricity from 0 to 120 degrees of knee flexion. Length patterns were considered isometric if there was less than 5 mm of length change throughout range of motion. RESULTS: The MPFL attaches from the posterior part of the medial epicondyle, to the superomedial patella, the under-surface of vastus medialis, and the quadriceps tendon. Optimal attachment points for an MPFL graft were the superior patella and the femoral attachment points of the MPFL (just distal to the adductor tubercle) and points posterior and inferior to this. CONCLUSION: We have defined the anatomy and kinematics of the MPFL with reconstruction of this ligament in mind.

Arthroplasty, Replacement, Knee↗
PubMed1998

Is there a future for hinged prostheses in primary total knee arthroplasty? A 20-year survivorship analysis of the Blauth prosthesis.

The Blauth prosthesis is a hinged total knee replacement. We have evaluated 422 consecutive primary total knee arthroplasties using this design in 330 patients with a maximum follow-up of 20 years (mean 6). The mean age of the patients at the time of operation was 70 years (29 to 87). Using endpoints of infection, removal because of aseptic loosening, removal for any cause, and the worst case as definitions of failure, the cumulative rates of survival at 20 years were 93.6%, 96.0%, 94.4% and 86.8%, respectively. The cumulative rate of survival of the patients themselves was 14.4% (24% in patients with osteoarthritis and 9% in these with rheumatoid arthritis) after 20 years. Our survivorship analysis shows that hinged knee prostheses, when they are biomechanically well designed, can yield a satisfactory long-term outcome, similar to those of the best prostheses of the resurfacing type. Hinged knee prostheses continue to be of value in patients with severe deformity or instability of the knee.

Adult↗
PubMed1991

[Computerized tomography in instability of the femoropatellar joint].

Compared with normal X-ray examination, a CT scan can give more information about patellar alignment, especially close to full extension of the knee-joint. We compared the normal knee-joints of 10 volunteers with the knee-joints of 15 patients (19 recurrent luxations, 5 habitual subluxations). We were able to distinguish between instabilities with and without changes seen on the X-ray pictures, making it possible to develop a systematic concept of treatment. In the case of recurrent dislocation with radiologically visible instability, surgical repair is the treatment of choice, while for habitual subluxation without radiologically visible instability the primary treatment of choice is conservative therapy with physiotherapy and muscle training. This is successful in most cases. If physiotherapy fails surgical repair is the next step in treatment. This dynamic type of investigation (the patella is stabilized by tension of the quadriceps femoris muscle) makes an objective judgement of the result of therapy possible.

Adult↗
PubMed1997

The effects of heating with ultrasound on knee joint displacement.

UNLABELLED: Heating with continuous wattage ultrasound combined with mobilization procedures is often used to treat ligament "tightness," but the effects of heat on ligament extensibility have not previously been studied in vivo. To address this problem, 25 young adults underwent knee joint displacement tests on a Genucom arthrometer before and after continuous wattage ultrasound (1 MHZ, 1.5 W/cm2 x 8 min). Preultrasound intrarater reliability (ICC; N = 11) was 0.87-0.98 for varus/valgus and recurvatum tests and 0.70-0.73 for anterior-posterior drawer tests. RESULTS: Continuous wattage ultrasound was associated with small increases in mean varus/valgus excursion at 0 degree and 20 degrees of knee flexion (p < or = .04) and in recurvatum excursion (p < or = .04) but not in anterior-posterior drawer excursion. The magnitude of the changes was 1.3 degrees or less and represented relative changes of 6.1-9.8%. CONCLUSION: Continuous wattage ultrasound at common clinical intensities made some knee ligaments slightly more extensible in normal subjects, although the magnitude of the effect was not deemed clinically significant.

Adult↗
PubMed2005

Clinical and radiological outcome of medial patellofemoral ligament reconstruction with a semitendinosus autograft for patella instability.

BACKGROUND: Recurrent patellar instability is a common problem after dislocation. The medial patellofemoral ligament (MPFL) contributes 40-80% of the total medial restraining forces. This study assessed the clinical and radiological outcome after a follow-up of 4 years after linear MPFL reconstruction using an ipsilateral Semitendinosus tendon autograft. STUDY DESIGN AND METHODS: 15 knees in 12 patients were examined with a mean of 47 months after linear reconstruction of the MPFL at a mean age of 30 years. 3 knees underwent previous surgery. 3 patients had mild trochlear dysplasia grade I or II, according to the classification of Dejour. If preoperative tibial tuberosity-trochlear groove distance (TTTG) was more than 15 mm, patients underwent additional medialisation of the tibial tuberosity (n=8) creating a similar postoperative situation for all patients. All patients were available for a postoperative evaluation, which consisted of a subjective questionnaire, the Kujala score, and the recording of potential patellar redislocation and apprehension. Patellar height and tilt was measured on plain radiographs. Postoperative CT scans were performed in patients with an additional tibial tuberosity-transfer. RESULTS: Postoperatively, one patient reported on recurrent bilateral redislocation. Physical examination however revealed no findings. Three knees presented with persistent patellar apprehension. Thirteen knees had improved subjectively after surgery. The mean Kujala score improved significantly from 55.0 to 85.7 points. The patellar tilt decreased significantly from 11.3 degrees to 9.2 degrees. Four knees had patella alta preoperatively, but only two at the latest follow-up visit. Previous surgery or additional trochlear dysplasia had no influence on the clinical outcome. CONCLUSION: MPFL reconstruction improves clinical symptoms, reduces the patellar tilt substantially, and may correct patella alta. Additional mild trochlear dysplasia did not compromise the outcome; however, this fact needs further attention in a larger study group.

Adult↗
PubMed1994

Extra-articular tenodesis for anterior cruciate ligament rupture in amateur skiers.

Thirty one amateur skiers with 33 knees which had had a symptomatic chronic rupture of the anterior cruciate ligament (ACL) treated with the Lemaire operation were reviewed retrospectively at an average of 4.5 years. Of the patients 23 were women. The operation failed to control symptoms in 17 out of the 33 knees. However the operation did control symptoms in 13 out of 19 knees in patients over 35 years old, compared with only three out of 14 knees in patients under 35 years old. Clinical and objective testing however showed that most knees were still unstable. Despite this 21 patients continued skiing. One patient with a successful result switched to playing tennis. Five patients gave up all sports. Four further patients, all under 35 years old, returned to skiing after an additional intra-articular reconstruction of the anterior cruciate ligament. An isolated extra-articular procedure in amateur skiers under 35 years old with symptomatic chronic ACL rupture is not recommended. They need at least an intra-articular reconstruction to control their symptoms and to stabilize the knee.

Adolescent↗
PubMed2000

Subchondral contusion of the knee caused by axial loading from dashboard impact: detection by magnetic resonance imaging.

We studied the occurrence of "bone bruises" of the knee resulting from dashboard impaction and detected by magnetic resonance imaging (MRI). We chose 21 knees of 20 front seat occupants in head-on motor vehicle collisions. To ensure all knees had received a significant axial load, patients selected had ipsilateral posterior hip dislocations and/or posterior wall acetabular fractures. Anteroposterior and lateral knee radiographs were negative for fracture in all cases. T1-weighted axial and sagittal MRI of each knee with a 1.5-T magnetron scanner revealed signal changes consistent with subchondral microfracture or bone bruise in 8 of the 21 knees. Previous cadaveric, animal, and MRI studies have suggested that such changes may be precursors of posttraumatic osteoarthritis. With the increasing incidence of serious lower extremity injury as a result of motor vehicle accidents, these occult injuries may significantly affect individuals and society.

Accidents, Traffic↗
PubMed2003

[The direct, dorsal approach to the treatment of unstable tibial posteromedial fracture-dislocations].

The surgical treatment of highly unstable tibial posteromedial fracture-dislocations (medial split fracture,Moore type I) is demanding and may cause significant problems. The anterior and the posteromedial approach require detachment of the medial capsuloligamental structures or arthrotomy of the knee joint. Neither of these operative techniques allow the optimal posterior positioning of the buttress plate in order to prevent caudal dislocation of the fragment during knee flexion. The published posterior approaches to the proximal tibia allow appropriate positioning of the anti-glide plate. However, these surgical exposures involve transsection of the semi-membranous and popliteal muscles as well as the partial dissection of the medial gastrocnemius muscle. We present a direct posterior approach and an operative treatment of medial split fractures with open reduction and internal fixation in a prone position. This position simplifies the reduction of the posteromedial fragment by hyperextension and axial traction, as well as osteosynthesis with lag screws and the placement of the buttress plate (radial T-plate). The surgical exposure requires minimal soft tissue dissection. The inferior spike of the fragment can be visualized by partial subperiosteal detachment the popliteal muscle,whereas the medial gastrocnemius muscle and the semi-membranous muscle are preserved. Due to the voluminous subcutaneous tissue in the posteromedial tibial aspect, the closure of the skin incision over the medial gastrocnemius muscle can be performed without difficulty. Three cases of tibial posteromedial fracture-dislocation were treated by the direct posterior approach in a prone position in January and February 2002. The present report shows that the direct posterior surgical technique allows optimal exposure, reduction and internal fixation of medial split fractures of the tibial plateau with minimal trauma.

Adult↗
PubMed2000

Mechanism-based pattern approach to classification of complex injuries of the knee depicted at MR imaging.

Complex knee injuries are common, often resulting from multiple forces: varus, valgus, hyperextension, hyperflexion, internal rotation, external rotation, anterior or posterior translation, and axial load. Certain combinations of forces are known to cause specific injury patterns. After a review of the literature, the authors developed a mechanism-based classification system based on patterns of bone marrow edema and ligament injury for complex knee injuries depicted at magnetic resonance imaging. The classification system takes into account knee position and forces and recognition of patterns of bone injury and complementary soft-tissue injury. Ten mechanism-based injury patterns were recognized: (a) pure hyperextension, (b) hyperextension with varus, (c) hyperextension with valgus, (d) pure valgus, (e) pure varus, (f) flexion with valgus and external rotation, (g) flexion with varus and internal rotation, (h) flexion with posterior tibial translation, (i) patellar dislocation (flexion, valgus, and internal rotation of femur on fixed tibia), and (j) direct trauma. Recognition of these patterns may help assess the full extent of knee injury, particularly at the posterolateral and posteromedial corners of the knee.

Anterior Cruciate Ligament Injuries↗
PubMed2005

Anatomy, function, and rehabilitation of the popliteus musculotendinous complex.

We present a clinical commentary of existing evidence regarding popliteus musculotendinous complex anatomy, biomechanics, muscle activation, and kinesthesia as they relate to functional knee joint rehabilitation. The popliteus appears to act as a dynamic guidance system for monitoring and controlling subtle transverse- and frontal-plane knee joint movements, controlling anterior-posterior lateral meniscus movement, unlocking and internally rotating the knee joint (tibia) during flexion initiation, assisting with 3-dimensional dynamic lower extremity postural stability during single-leg stance, preventing forward femoral dislocation on the tibia during flexed-knee stance, and providing for postural equilibrium adjustments during standing. These functions may be most important during mid-range knee flexion when capsuloligamentous struCtures are unable to function optimally. Because the popliteus musculotendinous complex has attachments that approximate the borders of both collateral ligaments, it has the potential for providing instantaneous 3-dimensional kinesthetic feedback of both medial and lateral tibiofemoral joint compartment function. Enhanced popliteus function as a kinesthetic knee joint monitor acting in synergy with dynamic hip muscular control of femoral internal rotation and adduction, and ankle subtalar muscular control of tibial abduction-external rotation or adduction-internal rotation, may help to prevent athletic knee joint injuries and facilitate recovery during rehabilitation by assisting the primary sagittal plane dynamic knee joint stabilization provided by the quadriceps femoris, hamstrings, and gastrocnemius.

Biomechanical Phenomena↗
PubMed2000

Natural history of unreduced congenital dislocation of the hip in adults.

The natural history of 33 patients with 43 unreduced congenital dislocations of the hip was reviewed. The average age at the first consultation was 50 years. Four were men and 29 were women. Ten patients had bilateral and 23 unilateral complete dislocation. Average follow-up lasted 9.2 years. At the final follow-up 23 hips and 18 knees were painful. Lumbago was observed in 6 of 15 patients under the age of 50 and in 14 of 18 patients over the age of 50 at the final follow-up. The average Harris hip scores at the first and final consultations were 69 and 70, respectively. The average dislocation index was increased in the standing more than in the lying position. In unilaterally dislocated hips the average femorotibial angles in the ipsilateral and contralateral knees to the dislocated hip were 172 and 179 deg, respectively. Lumbar degenerative scoliosis of more than 5 deg was observed in 16 patients.

Female↗
PubMed2001

Functional evaluation of the modified Elmslie-Trillat procedure for patello-femoral dysfunction.

A series of 28 knees in 27 patients were evaluated at an average of 36 months following surgical treatment for patella dislocation, patello-femoral pain, or a combination of both. All cases were treated by the modified Elmslie-Trillat procedure, which involves a lateral retinacular release and medialisation of the tibial tubercle on a distal pedicle. The evaluation included subjective, objective (Fulkerson and Kujala functional knee scores) and radiographic assessments. Subjectively, eight knees (28%) had excellent results, nine knees (33%) good results and seven knees (25%) fair results, accounting for an overall improvement of 86% over the preoperative status. All the knees in patients with a primary symptom of patella dislocation had an excellent or good subjective result, whilst only four knees (40%) in those patients with a primary symptom of pain and four knees (44%) in those with both pain and dislocation had a good or excellent result. The mean objective knee score was excellent for patients with dislocation only, and fair for those with only pain or both pain and dislocation. There have been no further episodes of dislocation in all patients. Six knees (21%) required later screw removal. The modified Elmslie-Trillat procedure produces a favourable outcome in patients with patella dislocation.

Adolescent↗
PubMed1996

Modified Hauser operation for patellar instability. Immediate mobilization of 35 knees, a 5-8 year follow-up study.

We performed a follow-up examination of 35 knees with chronic patellar instability treated by a modified Hauser operation: medialization and distalization of the tibial tubercle without dorsal transfer, and fixation of the tubercle rigidly with 2 cortical screws. Cast immobilization was not used and the patients were allowed to mobilize the knee immediately. The follow-up period was 6 (5-8) years. 27 of 35 knees were excellent or good at follow-up, while 8 patients were more or less dissatisfied with the result. 5 knees had arthrosis at follow-up. No severe complications occurred, nor did the rate of minor complications differ from earlier reports.

Adolescent↗
PubMed1987

[The role of the quadriceps muscle for the patello-femoral malalignment syndrome].

At knee extension on the Cybex Machine II (Lumex, Co. Ltd.), electromyograms (EMG) from the vastus medialis (M) and the vastus lateralis (L) were picked up by surface electrodes. The L/M ratio was calculated by the integrated value of the EMG and the power spectrum dealt with the frequency analysis of the EMG. There was a correlation between the L/M ratio and Q angle for the normal group, a constant relation for the hypermobile patella group, and an inverse correlation for the group with recurrent subluxation of patella. The vastus medialis (M)-dominant group, intermediate group and the vastus lateralis (L)-dominant group from the value of the L/M ratio was also classified. In the control group, subgroup 2 with clinical signs or their past histories around the knee included relatively more L-dominant than subgroup 1 without clinical signs. In the patello-femoral malalignment group, more cases were L-dominant.

Biomechanical Phenomena↗
PubMedDate not supplied

The diagnosis of knee motion limits, subluxations, and ligament injury.

The clinical diagnosis of knee ligament injuries requires the clinician to: 1) estimate the abnormal motion limits that occur in one or more of the six degrees of freedom that comprise three-dimensional motion; 2) determine the abnormal position (subluxation) of the medial and lateral tibiofemoral compartments; and 3) precisely define the anatomical structures injured and degree of that injury. To determine the clinician's ability to perform these tasks, we evaluated 11 knee surgeons' clinical examination for knee instability. The positions and motions included were measured in right-left cadaveric knees by a three-dimensional instrumented spacial linkage. We compared the clinicians' estimate of knee motion limits and subluxations with the actual measured values. Before and after the clinicians' examination, the three-dimensional limits of knee motion were measured in the knees in the laboratory under defined loading conditions. Also, in one knee, the ACL and superficial medial collateral ligament were cut and the examiners, none of whom were informed of the sectioning, were asked to arrive at a diagnosis. The results for all of the clinical instability tests were similar. There was wide variability between examiners in the starting position of knee flexion and tibial rotation and in the amount of tibial translation and rotation induced. Although some examiners displaced the knee to the maximal displacement limits obtained in the laboratory, others did not, by a substantial margin. This suggests a wide variation in the loads applied by examiners to the knee joint during the tests.(ABSTRACT TRUNCATED AT 250 WORDS)

Anterior Cruciate Ligament↗
PubMed2003

[Computed tomography of the patellofemoral alignment after arthroscopic reconstruction following patella dislocation].

PURPOSE: To evaluate the diagnostic impact of different CT-based measurements to analyze the patellofemoral alignment after arthroscopic reconstruction in patients with patella dislocation. MATERIALS AND METHODS: In 18 patients with dislocation of the patella, CT of the patellofemoral joint was performed after arthroscopic reconstruction. Various methods recommended in the literature were used to analyze the structure and the alignment of the patellofemoral joint with a relaxed quadriceps muscle. Axial CT scans were taken in four different knee flexion angles (15 degrees, 30 degrees, 45 degrees, 60 degrees ). RESULTS: After arthroscopic stabilization in patients with patella dislocation, only the lateral patellofemoral angle (15 degrees and 30 degrees knee flexion) and the congruence angle (15 degrees knee flexion) showed significant differences between the CT-measurements in the normal and the operated group. The differences of the remaining mean values were not significant due to a high standard deviation. With increasing flexion of the knee, the differences between the normal and the dislocation group almost disappeared. Only the lateral patellofemoral angle, the patella tilt and the lateral patella shift revealed differences between the normal and the group with recurrent dislocation in every degree of knee flexion. With increasing knee flexion above 30 degrees and especially at 60 degrees, the majority of the measured values returned to the normal range. CONCLUSIONS: For CT-measurements of the patellofemoral joint after arthroscopic stabilization, the patellofemoral angle and the congruence angle seemed to be most useful. The measurements of the patellofemoral joint should be taken in various degrees of knee flexion.

Adolescent↗
PubMed2006

Osteoarthritis of the hip and knee: sex and gender differences.

Osteoarthritis of the hip and knee is a leading cause of functional disability and compromised quality of life in older patients and a significant public health issue. Emerging research shows sex and gender differences in osteoarthritis which, to date, may not be appreciated by the orthopedic community. This article discusses sex and gender differences in osteoarthritis with a focus on disease involving the hip and knee. Understanding what we know (and do not know) about sex and gender differences in this disorder is critical to improving quality of care for our patients.

Anterior Cruciate Ligament Injuries↗