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Primary constrained condylar knee arthroplasty without stem extensions for the valgus knee.

UNLABELLED: Avoiding stem extensions in total knee arthroplasties may decrease operative time, prosthetic cost, and canal invasion at surgery. A constrained condylar knee implant without stem extensions also likely will be easier to revise and will eliminate the risk of end of stem pain. Our hypothesis was that a constrained condylar knee implant for primary severely deformed knees would show excellent midterm results with a low rate of aseptic loosening, even without diaphyseal-engaging stems. We retrospectively reviewed 70 consecutive primary constrained condylar knee implants without stem extensions from 1998 to 2001 in 61 patients with knees in 15 degrees valgus or greater. Forty-nine patients (55 knees) were followed up for 44.5 months (range, 2-6 years). Outcome was assessed using the Knee Society scoring system. Knee Society score and functional scores improved from 34 points and 40 points to 93 and 74 points, respectively. No radiographic loosening or wear was found. There were no peroneal nerve palsies, and no patients had flexion or medial instability. One patient was affected by chronic patellar dislocation. Constrained condylar knee implants in patients with severe valgus deformity resulted in pain relief and improved function, without substantial complications at midterm followup, without diaphyseal-engaging stem extensions. LEVEL OF EVIDENCE: Therapeutic study, Level IV (case series). See the Guidelines for Authors for a complete description of levels of evidence.

Aged↗

Treatment of recurrent patellar instability with a modification of the Roux-Goldthwait technique.

Recurrent instability of the patella may be a significant disability in the childhood and adolescent population. Numerous surgical procedures to address this instability have been described, with variable outcome. This has led to considerable confusion in the literature as to how to treat patellofemoral problems in children. This study retrospectively reviews 30 knees in 20 patients with chronic recurrent patellar instability who were treated with a modified Roux-Goldthwait technique including the release of contracted lateral structures by a single surgeon over a 13-year period, with an average of 6.2 years follow-up. By Insall's criteria, 26 knees had an excellent result, 3 good result, and 1 fair result. Ten patients evaluated using a dynamometer showed that strength achieved in the operated leg was greater than 90% in 8 patients and greater than 80% in 2 patients. Here, we report upon a single operation to treat patellar instability performed in the pediatric population with consistently excellent results.

Adolescent↗

Ultrastructural study of the extra-articular Leeds-Keio ligament prosthesis.

BACKGROUND: There have been several histological studies of the Leeds-Keio ligament in anterior cruciate ligament reconstruction, but there have been few of the Leeds-Keio ligament in the extra-articular portion. AIMS/METHODS: To report the histological and ultrastructural findings of two cases of medial patellofemoral ligament reconstruction using the Leeds-Keio ligament, removed 6.1 years and 8.7 years after implantation. RESULTS: In both cases, the tissue over the Leeds-Keio ligament was a ligament-like tissue. Electron microscopy showed that the diameter of the collagen fibrils in the tissue over the Leeds-Keio ligament was unimodal in the case investigated 6.1 years after implantation but bimodal in the case investigated after 8.7 years. CONCLUSIONS: The tissue over the Leeds-Keio ligament may continue to grow with prolonged periods of mechanical stress.

Adolescent↗

Arthritis of the canine stifle joint.

A survey of cadaver material was undertaken in order to determine the prevalence of arthritis of the canine stifle joint. One hundred and fifty unselected cadavers were obtained from veterinary practices for this purpose, and their stifle joints were radiographed and dissected to discover abnormalities. Thirty-one dogs (20 per cent) had stifle arthritis and in all except one the lesions were characteristic of osteoarthritis. In the exceptional case infection was the cause. A mechanical derangement was present in 20 of the 54 affected joints, in the form of rupture of the anterior cruciate ligament (10), meniscal tears (9) and patellar dislocation (1). The cause of the arthritis in the other 33 joints is unknown.

Animals↗

Surgical remodelling of the femoral trochlea: an experimental study.

Surgical deepening of the groove in the femoral trochlea is a technique commonly employed in the correction of patellar dislocation in dogs. In order to discover how this deep articular defect repairs the operation was studied experimentally in young goats. Observations were made on the appearance of the trochlea and the histologic changes that had taken place after approximately six, 12, and 40 weeks. The abraded groove became filled with fibrocartilage with a relatively smooth surface and it articulated freely with the patella. The majority of the replacement tissues arose by differentiation of the granulation tissue which initially filled the groove, but there appeared to have been some contribution made by the hyaline cartilage at the margins of the groove.

Animals↗

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↗

Anterior cruciate ligament injuries in patients with open physes.

From July 1988 to August 1989, six children with open physes and injuries to the anterior cruciate ligament were treated operatively. All injuries involved twisting episodes during sports activities. All six patients had meniscal abnormalities, and, additionally, one patient sustained a Grade III medical ligament tear and had a lateral patellar dislocation. Operative reconstruction used hamstring tendons and place a groove over the front of the tibia and a groove over the top of the femur without violation of the growth plates. The anterior cruciate ligament was primarily repaired (three patients) at the time of reconstruction, if possible. At 3 months, one patient underwent arthroscopic resection of adhesions for arthrofibrosis. There were no other complications. Five patients were evaluated with clinical examination, radiographs, magnetic resonance imaging, and functional testing at an average followup of 33.2 months (range, 25 to 38). Four of the five had returned to their preinjury level of sports participation. Manual maximum KT-1000 arthrometer side-to-side differences averaged 3.6 +/- 1.9 mm. The average Lysholm knee score was 95.2 +/- 2.5; the average Hospital for Special Surgery knee score was 96.6 +/- 2.3. There were no growth plate injuries. Despite the overall clinical stability, magnetic resonance image scans of the five patients consistently demonstrated areas of increased signal in the anterior cruciate ligament grafts.

Adolescent↗

Knee injuries in women collegiate rugby players.

We evaluated the prevalence and patterns of knee injuries in 810 women collegiate rugby players. Injuries that resulted in players missing at least one game were recorded and a questionnaire was used to delineate players' rugby and knee injury history. There were 76 total knee injuries in 58,296 exposures. This resulted in a 1.3 knee injury rate per 1000 exposures. Twenty-one anterior cruciate ligament tears were reported for a 0.36 incidence per 1000 exposures. Other injuries included meniscal tears (25), medical collateral ligament sprains (23), patellar dislocations (5), and posterior cruciate ligament tears (2). Sixty-one percent of the medial collateral ligament sprains occurred in rugby forwards and 67% of anterior cruciate ligament tears occurred in rugby backs. All other injuries occurred with equal frequency in backs and forwards. This study demonstrates that knee injury rates in women's collegiate rugby are similar to those reported for other women's collegiate sports. The overall rate of anterior cruciate ligament injury in women's rugby, however, is slightly higher than that reported for women soccer and basketball players.

Adolescent↗

Axial correction of pes varus by transverse-opening wedge osteotomy and T-plate fixation with beta-tricalcium phosphate (beta-TCP) transplantation in dachshunds.

Axial correction was performed surgically in two miniature dachshunds presenting with lateral patellar dislocation and limping caused by pes varus. Pes varus had resulted from asymmetric closure of the physis of the distal tibia. Prior to surgery, osteotomy was simulated by measuring X-ray films to determine the distance required for the wedge opening. Transverse-opening wedge osteotomy was performed on the medial side of the distal tibia, and beta-tricalcium phosphate (beta-TCP) was inserted in a wedge shape into the area created by the cuneiform osteotomy. Finally, the tibia was fixed by a veterinary 1.5/2.0-mm T-plate. Both dogs were able to walk a few days after surgery, and the lateral dislocation of the patella normalized almost completely in about one month. At two months, X-ray films showed that the implant had remained in position without any dislocation, and the beta-TCP had fused with the surrounding bone.

Animals↗

Acute haemarthrosis of the knee in athletes. A prospective study of 106 cases.

We made a prospective arthroscopic study of 106 skeletally mature male sportsmen with an average age of 28.35 years (16.8 to 44) who presented with an acute haemarthrosis of the knee due to sporting activities. We excluded those with patellar dislocations, radiographic bone injuries, extra-articular ligamentous lesions or a previous injury to the same joint. The anterior cruciate ligament (ACL) was intact in 35 patients, partially disrupted in 28 and completely ruptured in 43. In the patients with an ACL lesion, associated injuries included meniscal tears (17 patients), cartilaginous loose bodies (6), and minimal osteochondral fractures of the patella (2), the tibial plateau (3) or the femoral condyle (9). We found no age-related trend in the pattern of ACL injuries. Isolated injuries included one small osteochondral fracture of the patella, and one partial and one total disruption of the posterior cruciate ligament. Three patients had cartilaginous loose bodies, and no injury was detected in five. Acute traumatic haemarthrosis indicates a serious ligament injury until proved otherwise, and arthroscopy is needed to complement careful history and clinical examination. All cases with a tense effusion developing within 12 hours of injury should have an aspiration. If haemarthrosis is confirmed, urgent admission and arthroscopy are indicated.

Acute Disease↗

Patellar complications following distal femoral replacement after bone tumor resection.

BACKGROUND: Patellar complications following endoprosthetic reconstruction can occur as a result of anatomic, physiologic, and surgical reasons. Patellar impingement on tibial polyethylene is a complication of distal femoral replacement, and it is frequently related to inaccurate restoration of the joint line and to soft-tissue contracture. The purpose of our study was to determine the prevalence and type of patellar complications following distal femoral replacements after excisions of bone tumors. METHODS: The results of reconstruction with use of a rotating-hinge endoprosthesis following excision of a distal femoral tumor in forty-three patients were retrospectively reviewed. Patients were followed clinically and radiographically for a minimum of forty-eight months or until death. Pain status, functional scores, and the range of motion were determined from a prospectively maintained database. The ratio of the patellar tendon length to the height of the patellar tendon insertion, as described by Insall and Salvati, was calculated. In addition, we attempted to determine whether the position of the patella was associated with anterior knee pain or with the functional scores derived with use of the International Society of Limb Salvage (ISOLS) scoring system. RESULTS: Thirty-five patellar complications, including eleven cases of impingement, occurred in twenty-seven patients (63%). We found no difference, on the basis of our sample size, with regard to the presence of patellar pain, the range of motion, or the Insall-Salvati ratio between the patients with and those without impingement. The ratio of the patellar tendon length to the height of the patellar tendon insertion averaged 0.9 in the group with impingement and 1.4 in the group without impingement (p = 0.07). The ISOLS score averaged 21.2 points in the group with impingement compared with 24.2 points in the group without impingement (p = 0.01). Patella baja occurred in nine patients. The average ISOLS score (and standard deviation) was 20.1 +/- 4.4 points for the patients with patella baja compared with 24.8 +/- 3.9 points in the group with a normal patellar position (p = 0.004). Patellar fracture occurred in two patients, and osteonecrosis occurred in two patients. These patients were treated nonoperatively. CONCLUSIONS: Patellar complications are common after distal femoral resection and endoprosthetic reconstruction. Patellar impingement on the polyethylene tibial bearing surface is a more common and important complication of distal femoral replacement than has been reported to date. Patella baja is also a relatively common complication, which has a negative impact on knee function.

Adult↗

Focal fibrocartilaginous dysplasia of long bones: report of eight additional cases and literature review.

We report eight additional cases of focal fibrocartilaginous dysplasia (FFCD) in the proximal tibia (five), distal ulna (one), and distal femur (two). Spontaneous, complete resolution of the lesion was observed in two tibiae and one ulna. Three tibial lesions with genu varum deformity were managed with osteotomy. Two femoral FFCDs caused persistent or progressive deformity: one genu valgum with patellar dislocation, and one genu varum. These patients underwent concomitant deformity correction and lengthening by the Ilizarov method. The final results were satisfactory in all patients except one, who underwent valgus tibial osteotomy and developed mild postoperative genu valgum. The analysis of a total of 46 cases in the literature and our experience suggests that (a) FFCD has a wide histopathologic spectrum, ranging from purely dense, fibrous tendon-like tissue to benign fibrocartilaginous tissue; (b) at least 45% of tibial FFCD demonstrates progressive, spontaneous resolution; (c) in contrast, femoral and humeral FFCDs appear to have a slim possibility of spontaneous regression of the deformity; and (d) corrective osteotomy is indicated when the deformity is increasing or persistent, or when the existing deformity is severe enough to jeopardize adjacent joint mechanics and alignment.

Cartilage Diseases↗

Hemarthrosis after trauma to the pediatric knee joint: what is the value of magnetic resonance imaging in the diagnostic algorithm?

In children, compulsory arthroscopy for hemarthrosis after knee trauma is not justified because ligamentous and meniscal damage is rare. In a prospective study, we analyzed the diagnostic value of radiography, magnetic resonance imaging (MRI), and arthroscopy in 51 patients up to 14 years of age with acute knee trauma. Plain radiography revealed 16 osseous lesions (5 metaphyseal, 3 patellar, 4 physeal fractures, 3 avulsions of the tibial spine, and 1 osseous ligamentous tear). In 29 patients, the cause of hemarthrosis remained unclear. All patients were evaluated by MRI. A diagnosis could be assigned to all 29 patients. MRI demonstrated lesions in 38 patients. In addition, the following lesions were discovered: 8 patellar dislocations, 13 bruises, 1 rupture of the anterior cruciate ligament, 1 osteochondritis dissecans, and 13 joint effusions. In 13 patients, MRI was followed by arthroscopy to confirm the diagnosis. Both, MRI and arthroscopy missed two osteochondral fractures. In addition, three chondral lesions were not picked up by MRI. MRI is a reliable tool for assessing the extent of knee lesions in children.

Adolescent↗

Orthopaedic manifestations of Marinesco-Sjögren syndrome.

Two patients with Marinesco-Sjögren syndrome had striking orthopaedic abnormalities that seemed to arise from multiple areas of physeal growth arrest. Major involvement was seen in the distal femora, where bilateral hypoplasia of the lateral condyles resulted in progressive valgus, patellar dislocation, and quadriceps dysfunction. Marinesco-Sjögren syndrome seems to arise from an error in lysosomal handling of lipids. Timely orthopaedic intervention may be helpful in prolonging ambulation in these patients.

Bone Diseases, Developmental↗

[Total knee replacement in valgus knee].

OBJECTIVE: To investigate the methods and clinical results of total knee replacement (TKA) in patients with valgus knee deformity. METHODS: Between January 1996 and August 2004, 87 TKAs were performed by means of medial parapatellar approach, standard osteotomy and only lateral soft tissue release with posterior stabilized implants on 74 patients (11 men and 63 women) with valgus deformity. The average age at the time of operation was 62.93 years (range, 26-80 years). Clinical and radiographic evaluations including range of motion (ROM), Knee Society Score System (KSS) and the tibial and femur angle (T-F angle) were performed at follow-up. RESULTS: After a mean follow-up of 33.8 months (range, 5 months-9 years), the average ROM improved from 91 degrees (range, 70 degrees-120 degrees) preoperatively to 112.4 degrees (range, 80 degrees-130 degrees) postoperatively, the average KSS improved from 22.7 points (0-48 points) preoperatively to 81.7 points (range, 71-93 points) postoperatively. The average function score improved from 26.5 points preoperatively to 86.3 points postoperatively, the average T-F angle was corrected from 21.59 degrees (range, 12 degrees-40 degrees) of valgus preoperatively to 8.7 degrees (0 degrees-11 degrees) of valgus postoperatively. One knee had lightly instability at follow-up, one knee with patellar dislocation preoperatively had subdislocation postoperatively, no other complication occurred. CONCLUSIONS: The techniques of medial parapatellar approach, standard osteotomy and only lateral soft tissue release with posterior stabilized implants can correct a fixed valgus deformity very successfully in patients undergoing primary total knee replacement, and provides excellent results.

Adult↗

Results of total knee arthroplasty using the posterior stabilized condylar prosthesis. A report of 137 consecutive cases.

One hundred thirty-seven consecutive posterior stabilized total knee arthroplasties (TKAs) were reviewed. Average age of the patient was 61.1 years and length of postoperative follow-up period was 29.2 months. Patients were evaluated using the Hospital for Special Surgery (HSS) knee rating scores. Average preoperative scores improved from 52 to 92, postoperatively. Ninety-eight percent of patients had no pain or mild occasional pain postoperatively compared with 99% of patients experiencing severe to disabling pain preoperatively. Complications included one myocardial infarction, two deep venous thrombosis, one urinary tract infection, one patellar dislocation, and four wound problems. There were two incidences of seroma, one hematoma, and one deep infection requiring revision after joint debridement and systemic antibiotics. Also noted was one incidence of ligamentous laxity and one patella fracture.

Aged↗

Degenerative knee joint lesions in mice after a single intra-articular collagenase injection. A new model of osteoarthritis.

A single intra-articular injection with bacterial collagenase in the right knee joints of 10-week-old male C57bl10 mice led to osteoarthritic lesions within a few weeks in these joints. The collagenase-induced osteoarthritis was characterized by severe degenerative cartilage lesions on the medial side of the femorotibial joint associated with patellar dislocation to the medial side of the joint, sclerosis of subchondral bone below the cartilage erosions, osteophyte formation, and consequent deformity of the knee joints. The osteoarthritic alterations in the collagenase model closely resembled the changes observed in spontaneous osteoarthritis in aged mice. The intra-articular injection with collagenase probably results in damage to collagen type I-containing joint structures, such as tendons, ligaments and menisci, leading to an instable knee joint that results in the osteoarthritic joint lesions observed in this model. The collagenase-induced osteoarthritis model offers the possibility of studying experimental osteoarthritis in large animal groups of inbred strains within a restricted time span at low costs.

Animals↗

[Knee joint hemarthrosis--differential diagnostic considerations for planning an operation].

From 1980 to the end of 1988, arthroscopy has been performed on 620 patients with acute hemarthrosis of the knee joint. Of all the intraarticular lesions, 89.4% required surgery. Arthroscopy has changed in the last decade from diagnostic screening to invasive instrumentation for exact operative planing and alternative operative techniques. Hemarthrosis in stable knee joints was caused by minor lesions (7.84%) that did not require surgical procedures. Seventy-three patients had traumatic patellar dislocations--in 33 cases associated with chondral or osteochondral fractures. In 54.8% of the isolated medial retinacular ruptures, simple suture was performed in 14 cases--3 times arthroscopically and 11 times open, combined with lateral retinacular release without redislocation following. Associated chondral fracture indicated surgery in all cases. Isolated meniscus pathology (12.48%) was treated by arthroscopy alone, and refixation of the medial meniscus was carried out using the inside-out technique in 27 cases. Arthroscopic elevation of lateral tibia plateau fracture--indicated by type II fracture according to the AO classification--was performed in 3 cases with excellent results, and was associated with screw fixation and image intensification in 2 patients. Intercondylar eminence fracture is an excellent indication for arthroscopic refixation in the presence of the mono- or two-fragment type of fracture. ACL rupture is the main intra-articular pathology (64.8%) for hemarthrosis of the knee joint, which was diagnosed as an acute injury within the 1st week following trauma (51.04%). Anterior instability can be detected clinically if a careful examination with the Lachman test, combined with the missing end-point and pivot-shift test, is performed.(ABSTRACT TRUNCATED AT 250 WORDS)

Arthroscopy↗