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Unilateral congenital medial patellar luxation in a young llama was corrected by medial joint capsule release, tibial crest transposition, trochleoplasty, and lateral joint capsule imbrication. The techniques used were the same as described in the dog. One year after surgery, the llama was not lame, but had a valgus deformity originating at the stifle, most likely caused by lateral femoral condyle hypoplasia.
Diabetes mellitus is the leading cause of Charcot neuroarthropathy. The most common location is along the medial column of the foot. Over a 2-year period, the process can result in a severely deformed foot, which is highly prone to ulcers, infection, and subsequent amputation. To help identify the early stages of the disease process, the histories, physical examinations, and radiographs of 40 patients with 51 neuropathic feet were evaluated. We were able to identify five stages of Charcot deformities. Stage 0 is a clinical stage in which the patient presents with a locally swollen, warm, and often painful foot. Radiographs are negative and technetium 99 bone scan is markedly positive. Indium and gallium scans are normal. Stage 1, in addition to the clinical findings, demonstrates periarticular cysts, erosions, localized osteopenia, and sometimes diastases. Stage 2 is marked by joint subluxations, usually starting between the second cuneiform and the base of the second metatarsal and spreading laterally. Stage 3 is identified by joint dislocation and arch collapse. Stage 4 is the healed and stable end result of the process. Clinically, there is no temperature gradient between the two feet. Radiographically, there is bony trabeculation across joint spaces indicative of mature fusion. Treatment of stage 0 consists of limited weightbearing and close observation while the diagnosis becomes clear. Stage 1 is treated with casting followed by a University of California Biomechanics Lab orthosis (UCBL), to maintain the arch while allowing limited weightbearing. In stage 2, a partial weightbearing total contact cast followed by a Charcot restraint orthotic walker (CROW) is used. Surgery may be needed at this stage, while the joints are still reducible. Arthrodesis with rigid fixation is recommended. Stage 3 is treated with casting for the acute phase, then with a patellar-tendon-bearing ankle-foot orthosis, CROW, or caliper orthosis. If ulcers are present, they are treated with weekly local debridement, antibiotics, and total contact casting. Occasionally decompressive ostectomy is required. Stage 4 may need surgical removal of the bony prominences causing the nonhealing ulcers. Extra-depth shoes and pressure-relieving orthoses are also used. Twenty-five percent of our patients diagnosed and treated in the early stages (stages 0, 1 and 2) did not develop deformity. Surgery to prevent deformity is recommended early, before the destructive stage (stage 3). Close follow-up, especially in a noncompliant population is necessary.
OBJECTIVE: To investigate the repair of partial-thickness lesions in rat articular cartilage by combining cell transplantation with transfer of growth factor complementary DNA (cDNA). METHODS: Mesenchymal cells isolated from rib perichondrium were infected ex vivo with adenoviral vectors carrying bone morphogenetic protein 2 (BMP-2) or insulin-like growth factor 1 (IGF-1) cDNA. The cells were suspended in fibrin glue and applied to mechanically induced partial-thickness cartilage lesions in the patellar groove of the rat femur. The filling of the defects was quantified and the quality and integration of the newly formed tissue were assessed by histochemical and immunohistochemical methods. Uninfected cells or cells infected with a LacZ reporter gene vector served as controls. RESULTS: Transplanted cells were able to attach to the wounded articular cartilage and were not displaced from the lesions by joint movement. Cells infected with both adenoviral vectors AdBMP-2 and AdIGF-1 produced repair cartilage of hyaline morphology containing a type II collagen-positive but type I collagen-negative proteoglycan-rich matrix that restored the articular surface in most lesions. Uninfected cells either failed to fill up the defects or formed fibrous tissue mainly composed of type I collagen. Excessive cells were partially dislocated to the joint margins, leading to osteophyte formation there if AdBMP-2-infected cells were used. These adverse effects, however, were not seen with AdIGF-1-infected cells. CONCLUSION: Stimulation of perichondrium-derived mesenchymal cells by transfer of growth factor cDNA in a partial-thickness defect model allows for satisfactory cartilage restoration by a repair tissue comparable with hyaline articular cartilage.
Inflammation models for the assessment of anti-rheumatic drug activity utilize a variety of stimuli and sites. However, the determination of cartilage and bone degradation remains time consuming and problematic. A rapid rat model of Mycobacterium tuberculosis monoarticular arthritis with induces of inflammation, as well as patellar cartilage proteoglycan and bone degradation has been reported. This study characterizes this model with respect to the actions of anti-rheumatic drugs. Dexamethasone, cyclosporin and prednisolone inhibited all three parameters. Methotrexate inhibited joint inflammation alone, whilst azathioprine was without effect. Levamisole inhibited cartilage and bone degradation without affecting joint inflammation. NSAIDs were divided in their actions. Naproxen, piroxicam, diclofenac and tiaprofenic acid all inhibited joint inflammation and bone loss, but naproxen and piroxicam both significantly potentiated cartilage proteoglycan loss. This model appears to rely on cellular recruitment at this early stage, the anti-metabolites being ineffective. The modulation of inflammation can result in a protection against cartilage and bone damage in arthritis; however, certain NSAIDs are detrimental to cartilage integrity. The pharmacological manipulation of inflammatory arthritis can therefore dislocate inflammation from its effects on tissue destruction.
Medial transfer of the tibial tuberosity has been commonly used for treatment of recurrent dislocation of the patella and patellofemoral malalignment. In this study, six fresh human cadaveric knees were used. Static intrajoint loads were recorded using Fuji Prescale pressure-sensitive film for contact pressure and contact area determination in a closed kinetic chain knee testing protocol. Peak pressures, average contact pressures, and contact areas of the patellofemoral and tibiofemoral joints were calculated on native intact knee specimens and after tibial tuberosity transfer. All native intact knee specimens had a normal Q angle. Medialization of the tibial tuberosity significantly increased the patellofemoral contact pressure. Medial displacement of the tibial tuberosity also significantly increased the average contact pressure of the medial tibiofemoral compartment and changed the balance of tibiofemoral joint loading. The results of our study suggest that caution should be used when transferring a patellar tendon in the face of a preexisting normal Q angle as this will result in abnormally high peak pressure within the tibiofemoral joint. Overmedialization of the tibial tuberosity should be avoided in the varus knee, the knee after medial meniscectomy, and the knee with preexisting degenerative arthritis of the medial compartment.
By means of motion-triggered MRT it has been possible for the first time to demonstrate movements in the patello-femoral joint by means of MRT. Patello-femoral movement was studied during active extension of the knee between 30 degrees flexion and complete extension. The knees of 5 normal females and 7 normal males were studied together with 2 women with recurrent lateral patellar luxation. In normal women there was an average 16 degrees (10 to 18 degrees), in men an average of 12 degrees (10 to 14 degrees) of lateralisation of the patella during complete extension of the knee. In 1 patient there was 10 degrees medial displacement of the patella before extension. In 2 knees with recurrent lateral subluxation there was a 20 and 24 degrees displacement of the patella.
Fifty-eight patients (69 knees) treated with the Kinematic Rotating Hinged knee prosthesis for complex primary and salvage revision total knee arthroplasty were followed up for an average of 75.2 months (range, 24-199 months). The indications for use of the Kinematic Rotating Hinged knee prosthesis included severe bone loss combined with ligamentous instability (30 knees), nonunion of a periprosthetic fracture (10 knees), an acute periprosthetic fracture (nine knees), severe collateral ligamentous instability (five knees), reimplantation for infection (six knees), nonunion of a supracondylar femoral fracture (four knees), congenital dislocation of the knee (three knees), and treatment of a severely comminuted distal femur (two knees). At the time of surgery, the average patient age was 72 years (range, 46-92 years). Preoperatively, knee extension averaged 4.94 degrees (range, 0 degrees-40 degrees) and flexion averaged 81 degrees (range, 15 degrees-125 degrees). At final followup, knee extension averaged 1.25 degrees (range, -5 degrees-25 degrees) and flexion averaged 94.2 degrees (range, 5 degrees-125 degrees). The preoperative Knee Society Knee score averaged 40.3 points (range, 2-93 points) and improved to 77 points (range, 33-99 points) at final followup. Complications were numerous: 23 (32%) patients experienced at least one complication and 12 (17%) patients had two or more complications. Deep periprosthetic infection was the most common complication (14.5%), followed by patellar complications (13%), and prosthetic component breakage (10%). During the period of this study, there were 15,798 primary and 2673 revision total knee arthroplasties done at the authors' institution. The patients receiving a Kinematic Rotating Hinged knee prosthesis represent a highly complex and small subset (0.37%) of the overall population having knee arthroplasty. Although the use of the Kinematic Rotating Hinged knee prosthesis for these limited indications has been useful for the authors, the incidence of complications and the poor outcome of these complications is disconcerting. Hinged total knee arthroplasty should be reserved for the final salvage option of the treatment options available when doing complex primary and salvage revision knee arthroplasties.
Ipsilateral femur fracture, patellar fracture, and tibial avulsion fractures of anterior and posterior cruciate ligament injuries are reported. We know of no other report of an injury such as this in the literature. We sutured the tibial avulsion fractures by transtibial suturing technique and internally fixated the femur by intramedullary interlocking nailing 2 weeks after the trauma. After 1 year the results were evaluated as very good. Early surgical repair is valuable in these injuries.
We examined 54 patients (60 knees) referred to us because of their failure to improve, or because of a worsening of their preoperative symptoms, following an arthroscopic lateral retinacular release. Thirty knees developed medial subluxation of the patella postoperatively. This disabling condition is new to us. It is previously unreported as a complication of arthroscopic lateral retinacular release. Anterior knee pain was the only reported preoperative symptom in 14 knees. Sixteen knees had a preoperative diagnosis of lateral patellar subluxation on the basis of a positive apprehension sign only. Eighteen of 30 knees had no surgery of the extensor mechanism other than the arthroscopic lateral release. The remainder additionally underwent varying types and numbers of operations in an attempt to resolve their disability. CAT scan evaluation of three patients who volunteered for the procedure demonstrated severe atrophy and retraction of the vastus lateralis. Loss of this dynamic lateral stabilizer contributed to the medial subluxation of the patella.
The patellar height was measured according to the index of Caton and Deschamps. The normal index equals 1, the patella considered as being high with an index of 1.2 or greater. The authors reviewed 50 patients presenting with such an anomaly in patellar height to verify whether this patella alta said to be idiopathic was simply a radiographic sign or represented a true anatomic and clinical entity. 61 knees were hence operated on between 1963 and 1988, 50% of which had a lowering of the tibial tuberosity. In 8 cases, the lowering was performed secondarily, after a failure of the first operation to correct the anomaly. The mean pre-operative index of patellar height was 1.34 and the trochlea appeared indisputably dysplastic in 50 of the 61 cases. The mean age at the time of surgery was 17 years. Medial translation of the tibial tuberosity averaged 9.5 mm and the lowering 7 mm allowing a normalization of the patellar index. 76.8% of patients had a perfect post-operative stability, evaluated as a score of 8 or 9 on the ARPEGE scale. At the completion of this study it appeared that patella alta is rarely an isolated finding and is most often part of a regional patello-femoral dysplasia. Its existence, when responsible for a functional problem, must absolutely be taken into account and treated to obtain a satisfactory result.
Medial patella luxation is a common orthopedic problem of toy and miniature breed dogs with a complex and poorly understood pathogenesis. Joint pathology increases with age and luxation grade, and surgical correction should be performed at the earliest opportunity to limit further development of skeletal abnormalities or degenerative joint disease. Combination of trochlear wedge recession or tibial crest transposition with joint imbrication-capsulectomy are sufficient to correct patella luxation in most dogs. Surgical correction of patella luxation grades 1, 2, or 3 results generally in a successful clinical outcome, whereas surgical correction of grade 4 patella luxations carries a guarded prognosis in the young dog.
Diagnosis and treatment of diseases of the foot, infectious arthritis, angular limb deformities, patellar luxation, tendon contracture and injuries, and fractures encountered in sheep, goats, llamas, and deer are reviewed. These species share similar orthopedic problems to cattle, but management conditions, particularly for pet animals, may place special demands on the veterinarian treating these disease conditions. The mild temperament and relatively small body size of these animals make them excellent candidates for treatment of orthopedic problems often not amenable to practical treatment in larger or more fractious animals.
In 1979, using the name "small patella syndrome", Scott and Taor described a family in which hypoplasia or aplasia of the patella was inherited by autosomal dominant transmission. Hip dysplasias and pelvic changes accompanying the patellar changes have also been observed in some cases. On the basis of three personal observations this dysplasia syndrome is described in more detail and compared with the other syndromes involving the kneecap and pelvis. One case was discovered as a result of a femoropatellar pain syndrome, a second because of slight functional disturbances. The third case was a chance finding. Although, in two of the cases, several affections of the locomotor apparatus were found in the patients' families, it could not be confirmed that the syndrome was hereditary.
BACKGROUND: Although the LCS (low contact stress) rotating-platform mobile-bearing knee replacement has been used extensively, there have been few intermediate or long-term clinical and radiographic follow-up studies evaluating the device. The purpose of this study was to report the nine to twelve-year results of a consecutive series of patients who had a primary total knee replacement performed with this device. METHODS: Between November 1985 and November 1988, the senior author (R. C. J.) performed 119 consecutive total knee arthroplasties in eighty-six patients with LCS rotating-platform femoral and tibial components and a Townley all-polyethylene dome patellar component. All components were fixed with cement. The average age of the patients at the time of the operation was seventy years (range, thirty-seven to eighty-eight years). Fifty-two patients (seventy-six knees) were female, and thirty-four patients (forty-three knees) were male. The patients were evaluated with clinical knee ratings and radiographic analysis nine to twelve years following the knee replacement. RESULTS: At the time of the nine to twelve-year follow-up, sixty-four patients (eighty-six knees) were alive, eighteen patients (twenty-eight knees) had died, and four patients (five knees) had been lost to follow-up. Of the 114 knees in the eighty-two patients for whom the final outcome was known, none required a reoperation and none had a dislocation of the mobile-bearing prosthesis. For the forty-five patients (sixty-six knees) who returned for final clinical and radiographic follow-up examinations at nine to twelve years, the average clinical and functional Knee Society ratings were 30 points (range, 2 to 70 points) and 44 points (range, 0 to 80 points) preoperatively and 90 points (range, 63 to 102 points) and 75 points (range, 30 to 100 points) at the final follow-up evaluation. The average Hospital for Special Surgery knee rating was 57 points (range, 28 to 80 points) preoperatively and 84 points (range, 59 to 97 points) at the final follow-up evaluation. The average active range of knee flexion was from 0 degrees (range, 0 to 10 degrees) to 102 degrees (range, 15 to 120 degrees) at the final follow-up evaluation. Seven of the sixty-six knees were painful anteriorly. There was no periprosthetic osteolysis and no evidence of loosening on follow-up radiographs. CONCLUSIONS: After nine to twelve years of follow-up, the cemented LCS rotating-platform knee replacement was found to be performing well, with durable clinical and radiographic results.
We prospectively determined the frequency of atlantoaxial subluxation in a group of patients with systemic lupus erythematosus (SLE) and analyzed its relationship with tendinous laxity, Jaccoud's syndrome and other features of the disease. Five of 59 patients (8.5%) had atlantoaxial subluxation. No patient presented atlantoaxial subluxation in neutral lateral cervical radiographs but all 5 had anterior atlantoaxial subluxation in full flexion films; one patient also had lateral subluxation. The 5 patients with atlantoaxial subluxation were compared with the remaining 54. Mean SLE disease duration was longer in patients with atlantoaxial subluxation (12 years) than in those without (6.6 years) (p less than 0.01). Jaccoud's syndrome, patellar tendon elongation and articular hypermobility were significantly more frequent in patients with atlantoaxial subluxation. The presence or history of arthritis failed to distinguish patients with and without atlantoaxial subluxation, while chronic renal failure and increased serum parathyroid hormone levels were significantly associated to the presence of atlantoaxial subluxation. We suggest that atlantoaxial subluxation is further evidence of tendinous alterations seen in patients with SLE.
The endoscopic single incision technique for anterior cruciate ligament (ACL) reconstruction with a femoral half-tunnel may lead to a graft/tunnel mismatch and subsequent protrusion of the block from the tibial tunnel. The typical tibial fixation with an interference screw is not possible in these cases. Fixation with staples in a bony groove inferior to the tunnel outlet can be used as an alternative technique. Current literature does not provide biomechanical data of either fixation technique in a human model. This study was performed to evaluate the primary biomechanical parameters of this technique compared with a standard interference screw fixation of the block. Fifty-five fresh-frozen relatively young (mean age 44 years) human cadaver knee joints were used. Grafts were harvested from the patellar tendon midportion with bone blocks of 25 mm length and 9 mm width. A 10-mm tibial tunnel was drilled from the anteromedial cortex to the center of the tibial insertion of the ACL. Three different sizes of interference screws (7 x 30, 9 x 20, 9 x 30 mm) were chosen as a standard control procedure (n = 40). For tibial bone-block fixation the graft was placed through the tunnel, and the screw was then inserted on the cancellous or the cortical surface, respectively. Fifteen knees were treated by staple fixation. A groove was created inferior to the tunnel outlet with a chisel. The bone block was fixed in this groove with two barbed stainless steel staples. Tensile testing in both groups was carried out under an axial load parallel to the tibial tunnel in a Zwick testing machine with a velocity of 1 mm/s. Dislocation of the graft and stiffness were calculated at 175 N load. Maximum load to failure using interference screws varied between 506 and 758 N. Load to failure using staples was 588 N. Dislocation of the graft ranged between 3.8 and 4.7 mm for interference screw fixation and was 4.7 mm for staples. Stiffness calculated at 175 N load was significantly higher in staple fixation. With either fixation technique, the recorded failure loads were sufficient to withstand the graft loads which are to be expected during the rehabilitation period. Staple fixation of the bone block outside of the tunnel resulted in a fixation strength comparable to interference screw fixation.
Forty-two knees with symptomatic mediopatellar plicae (shelves) were managed using the operative method under local anesthesia. Of these, thirty-one knees had isolated mediopatellar plicae, and eleven had other associated intra-articular pathologic condition, such as meniscal tear, lateral patellar tracking, osteochondritis dissecans, and minor osteoarthritic changes. The clinical results were excellent or good in thirty-seven (88%) patients, fair in five patients after an average follow-up of twenty-five months. No case showed deterioration after surgery. Because there are no definitive criteria for the indication of shelf resection, arthroscopic resection of the shelf under local anesthesia is recommended if there is any possibility of it being the cause of knee pain.
This study was based on the unexpected observation of lateral patellofemoral subluxation in the varus osteoarthritic knee. Standardized radiographs of 109 knees (65 patients with osteoarthritis) were selected randomly from the authors' database and retrospectively reviewed. Hip-knee-ankle alignment data were correlated with patellofemoral subluxation and tilt, as well as with radiographic patellofemoral grades for arthrosis. The amount and site of patellofemoral arthrosis were correlated with patellar position and limb alignment. Patellae that were located centrally in the trochlear groove had the lowest radiographic score for arthrosis. Subluxation of the patella, either medially or laterally, was correlated with increased radiographic scores. Limb alignment was not correlated with the radiographic score. A significant percentage of varus knees (28%) had unexpected lateral subluxation of the patella. This observation has not been reported previously. It may have an impact on surgical decision-making for total knee arthroplasty and osteotomy.