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PubMed2001

Rapid recovery after oxford unicompartmental arthroplasty through a short incision.

Forty Oxford medial unicompartmental arthroplasties (UCAs) were performed through a short incision medial to the patellar tendon, without dislocation of the patella, using updated instruments (Oxford Knee Phase III, Biomet Ltd., Bridgend, UK). The rate of recovery of these knees (measured by the time taken to achieve straight-leg raising, 70 degrees of flexion, and independent stair climbing) was compared with that of 20 Oxford UCAs performed through an open approach with dislocation of the patella. Both groups were compared with 40 AGC (Biomet) total knee arthroplasties performed for osteoarthritis during the same time period. The average rate of recovery after the short-incision UCA was twice as fast as after open UCA and 3 times as fast as after total knee arthroplasty. Accuracy of implantation, assessed from 11 variables seen on fluoroscopically centered postoperative radiographs, was the same after UCA by the short-incision approach as after the open approach, suggesting that the short-term advantage of increased speed of recovery was gained without affecting the long-term results. We now employ the short incision with the phase III instruments for all UCAs.

Aged↗
PubMedDate not supplied

Avulsion of the popliteus tendon.

Isolated avulsion of the popliteus tendon occurred in a 13-year-old patient who stepped awkwardly from a bus. This report of injury is of special interest because the forces are easy to interpret and reflect the expected mechanism of injury to the popliteus muscle-tendon complex. Furthermore, the injury has many features that may be confused with patellar subluxation and dislocation.

Adolescent↗
PubMed2000

[Revision in non-infected total knee arthroplasty: an analysis of 69 consecutive cases].

PURPOSE OF THE STUDY: We reviewed 69 consecutive cases of total knee arthroplasty revisions to analyze the causes of failure. MATERIAL AND METHODS: Sixty-nine total knee arthroplasty revisions were required between 1990 and 1997 for non-septic failure. Five categories of failures were identified: 30 loosenings including 11 with an initial malposition (varus position of the tibial component in 8 cases), 14 laxities (medial in 5, lateral in 5 and anteroposterior in 4), 11 stiff knees with no other clinical or radiological anomaly, 6 patellar failures (2 dislocations, 2 cases of excessive wear, 2 painful knees with a Freeman prosthesis), and 8 cases of painful knees with no other detectable anomaly. RESULTS: A three-phase reconstruction procedure was used after removing the failing TKA: 1) reconstruction of the tibia with replacement of lost bone, 2) reconstruction of the femur with balanced flexion determining the size of the implant, 3) balanced extension determining the distal/proximal position of the femoral component. A "simple" sliding prosthesis was used in 16 cases, a modular reconstruction prosthesis in 40 cases and a hinge prosthesis in 13 cases. Mean follow-up for functional and radiographic assessment after revision surgery was 37 months (59 cases) with a minimum follow-up of 1 year. The best outcome was observed in the "loosening", "laxity", and "stiffness" patients. Outcome was less favorable for the group "isolated pain" with IKS functional scores of 35.5 +/- 16 and 52.5 +/- 21. DISCUSSION: In 36 p. 100 of cases, TKA failure was related to a technical mistake (component malposition, poor ligament alignment). In 33 p. 100, failure was patient related (multiple procedures, congenital hip dysplasia, rheumatoid arthritis.). Outcome after revision TKA was less favorable than after primary TKA, particularly in case of painful knees with no other detectable anomaly. CONCLUSION: Surgical revision of TKA must follow a rigorous procedure with a detailed preoperative work-up. The decision for revision must not be made unless a precise anomaly has been identified.

Adult↗
PubMed1997

Congenital deficiency of the fibula with ipsilateral iliac horn and absence of the kidney.

Congenital deficiency of the fibula is sometimes accompanied by femoral hypoplasia, genu valgum, patellar a/hypoplasia or dislocation, tibial bowing, foot deformity, and toe deficiency in the affected limb. 'Iliac horns' are bony projections extending posterolaterally from the ilium and considered to be pathognomonic of nail-patella syndrome. We report a 5-year-old Japanese girl with congenital complete deficiency of the left fibula, ipsilateral iliac horn and absence of the left kidney.

Female↗
PubMed1989

Arthroscopic management of the patellar clunk syndrome following posterior stabilized total knee arthroplasty.

The patellofemoral articulation in total knee arthroplasty can give rise to postoperative complications, such as patellar fracture, subluxation, or dislocation. The accumulation of hypertrophic fibrous tissue at the superior margin of the patellar button can give rise to catching or "clunking" of the extensor mechanism. Open surgical excision of this mass is successful in alleviating symptoms but runs the risk of infection and wound complications and delays postoperative mobilization. Arthroscopic resection with motorized instrumentation is highly successful, offers less risk of infection, and allows rapid postoperative mobilization.

Aged↗
PubMed1994

Results of nonmetal-backed, high-density polyethylene, biconvex patellar prostheses. A 5-7-year follow-up evaluation.

This study evaluates the clinical and radiographic results of an all-polyethylene, biconvex, dome-shaped patellar prosthesis with precise instrumentation implanted in 53 knees with a minimum follow-up period of 5 years (average, 6.3 years; range, 5.0-7.1 years). The mean patient age was 70.9 years (range, 18.0-89.0 years). The mean Hospital for Special Surgery knee rating score was 63.6 before surgery and 83.4 after surgery. There was no fracture of the patella, no implant failure, or radiographic loosening of the prosthesis. Patellar complications consisted of two dislocations secondary to trauma and one case of patellar subluxation. Several radiographic parameters were measured. Means and SDs were computed for: (1) patellar tilt, as measured from a line between the anterior limits of the femoral condyles and the patella, which showed no significant difference after surgery (3.01 degrees +/- 5.12 degrees) compared to before surgery (3.73 degrees +/- 5.44 degrees); (2) the angle between the patellar component and the residual bone was -0.04 degrees +/- 2.04 degrees, with every case in the normal range (+/- 5 degrees); (3) there was no significant difference between pre- and postoperative patellar length, patellar thickness, or articular length of the patella; (4) the patellar height showed a small but statistically significant difference after surgery (2.69 +/- .64 cm) and before surgery (2.94 +/- .72 cm); (5) the distance from the tibial tubercle to the joint line did not differ significantly between preoperative (2.73 +/- 0.34 cm) and postoperative (3.06 +/- 0.36 cm) measurements; and (6) the distance from the center of the tibial plateau to the center line of the tibial prosthesis was 1.34 +/- 0.32 cm. These results are superior to previously reported series.

Aged↗
PubMed2003

[Evaluation of patello-femoral joint congruity following total knee arthroplasties].

OBJECTIVES: Complications associated with the patellar component have an important place for revision procedures following total knee arthroplasty (TKA). We evaluated the patello-femoral congruity both clinically and radiologically after TKAs performed with polyethylene patellar components. METHODS: The study included 60 knees of 55 patients (45 females, 10 males; mean age 66 years; range 33-82 years). Clinically, all patients were evaluated with respect to pain, knee functions, and range of motion of the knee joint. Antero-posterior, lateral, and patellar tangential radiographs were obtained. According to the tangential radiographs, the patients were divided into three groups; normal (group A), abnormal angular values without subluxation (group B), and the existence of subluxation, dislocation, or a fracture (group C). Patellar height, variations in the joint line, and patellar coverage by the component were measured on lateral radiographs. Patients with normal patellar congruity and patellar subluxation were compared. The mean follow-up period was 40 months (range 12 to 88 months). RESULTS: No significant differences were found between the three groups with respect to pain and range of motion of the knee joint; however, functional scores differed significantly (p=0.019). Radiologically, the mean valgus angles were not significantly different. According to the location of the patellar component on tangential radiographs, group A, group B, and group C included 39 knees (65.0%), 11 knees (18.3%), and 10 knees (16.7%), respectively. Measurements on lateral radiographs did not yield significant differences between patients with normal patellar congruity and patellar subluxation. CONCLUSION: Patellar subluxation should be investigated on tangential radiographs following TKA because lateral radiographs of the knee fail to show patello-femoral problems.

Adult↗
PubMed1977

Patellar-tendon transfer by the slot-block method for recurrent subluxation and dislocation of the patella.

In sixty-five knees followed for an average of 4.5 years after treatment of subluxation or dislocation of the patella by the slot-block method of medial patellar-tendon transfer, the results were satisfactory in fifty-four (83%) and unsatisfactory in eleven (17%). Recurrent subluxation or dislocation occurred in three (5%) of the knees and was attributed to insufficient displacement. Chondromalacia of the patella became worse after transfer in three of the sixty-two knees in which the distal realignment was technically correct. Two knees (3%) required patellectomy because of patellofemoral symptoms and there were nineteen complications in seventeen knees, including loss of motion in six, wound infection in six, displacement of the bone block in three, recurrent dislocation in three, and rupture of the patellar ligament in one. The method is believed to give superior results but it is technically demanding.

Humans↗
PubMed2004

[Patellar instability: arthroscopic surgery, indications and techniques].

A significant incidence of knee pain and disability arises from patellofemoral disorders. An accurate diagnosis relies both on a comprehensive history and a careful physical examination; radiologic modalities also play an important part in the diagnosis and follow-up. Most patellofemoral disorders can be examined in three groups: pain due to soft tissue abnormalities, patellar instability, and patellofemoral osteoarthritis. Conservative therapy can be successful in many patellofemoral disorders. Surgical treatment consists of lateral release, medial plication and reconstruction of the medial patellofemoral ligament, proximal and distal realignments, patellar osteotomies, and patellectomy. In traumatic dislocations primary reconstruction or arthroscopy assisted medial stabilization can be performed.

Arthroscopy↗
PubMed1993

[Biomechanical studies of change in the patellar tendon after transplant removal].

The reconstruction of the anterior cruciate ligament deficient knee with the patellar tendon is the "gold standard". Dislocation of the patella, rupture of the patellar tendon and fracture of the patella were reported to occur. In this biomechanical investigation on the changes of the patellar tendon following harvesting of a graft, 51 sheep knee underwent destructive testing at t0 (n = 11), 4 weeks p.op. (n = 5), 3 months p.op. (n = 14), 6 months p.op. (n = 15), and 12 months p.op. (n = 6). Harvesting of a graft produces a stiffness and strength of the patellar tendon of 50-70% of normal. There was no significant change of free patellar tendon length up to 12 months p.op. The cross-sectional area is definitely increased (p < 0.05). The tensile stress is always above normal, nevertheless the strength shows a massive decline until 6 months p.op. and does not regain normal strength by one year p.op. Stiffness shows comparable biomechanical pattern like tensile stress. There are time-dependent changes, the structural weakness is compensated by an increase of cross-sectional area. There is no restitution of the patellar tendon ad integrum, the remainder is a defect with scar tissue and alterated biomechanical properties. Revision surgery using the same host patellar tendon cannot be recommended.

Animals↗
PubMed1988

Patellofemoral problems following total knee arthroplasty.

We reviewed 350 knee arthroplasties performed between 1977 and 1984 for patellar problems. Seventeen knees with four types of patellofemoral complications were found. The diagnosis in both the group of 350 and the study group of 17 knees was evenly distributed between rheumatoid arthritis and osteoarthritis. The complication rate was 4.9%. Follow-up ranged from one to nine years post-complication. Two knees had two different complications, providing a total of 19 complications with five loosenings, three fractures of the patella, one fracture of the patellar component, and ten subluxations or dislocations. Sixteen revision surgical procedures were performed on 11 knees. Six knees were managed nonoperatively. In the four knees with multiple surgeries, one of the complications was patellar subluxation or dislocation. Only one patient was dissatisfied with his result; however, this included both knees. Patellar complications continue to be recognized as a frequent cause of problems after total knee arthroplasty. We recommend nonoperative management of patellar fractures, revision of implant with loosening or component fracture, and careful selection of realignment procedures.

Aged↗
PubMed1989

[Femoropatellar complications of 87 total condylar and Insall Burstein knee joint prostheses].

In a group of 87 total knee joint prostheses with posterior stabilization, 18 femoro patellar complications happened. Fractures, loosening, dislocations and subluxations are relatively rare. The persistence of residual patellar pain was more frequent with a high proportion of femoro-patellar derangement syndrome (FPDS). This last complication was specific of posterior stabilization model (MK II) and its origin is related to the formation of a synovial pannus in front of intercondylar region. In one case, it was surgically removed. The existence of this "FPDS" is statistically correlated with lowering of the patella, posterior position of tibial tuberosity and excessive thickness of the patellar implant complex.

Aged↗
PubMed1992

Patellar band for patellofemoral disorders: results and indications.

In patellofemoral disorders, some cases respond well to conservative management thus the authors' initial treatment is conservative. The Patellar Band (PB) was reported previously (Nakamura et al., 1987). Since then the indications for the band have been investigated. Sixty four patients treated by the PB without operative treatment were classified into eight groups. The Severity of Dysfunction (SOD) was assessed by three grades. The First Grade is dull pain after walking or running for a long distance, the Second Grade is sharp pain on climbing up and down stairs, the Third Grade is a feeling of insecurity. The grouping was as follows: Group Ia - plica syndrome with first Grade of SOD and Ib with Second Grade of SOD. Group IIa - chondromalacia with First Grade of SOD and IIb with Second Grade of SOD. Group III - maltracking patella with patellar pain on flexion. Group IVa - subluxation or dislocation of patella with no previous history of patellar symptom and IVb - recurrent dislocation. Group V - degenerative change of the patella. The PB has been proved to be most effective in Groups Ia, IIa and IVb although it is beneficial in half the cases in Groups IIb and III. The subluxation of the patella was partially reduced without recurrence of dislocation during sports activity and the feeling of insecurity was relieved by the PB. The overall results were not related to age or activity level of the patient. The indication of the band for painful knees was not clearly determined in this study. In all operated cases, it was effective for postoperative instability after lateral release of the retinaculum.

Activities of Daily Living↗
PubMed2004

Minimally invasive total knee arthroplasty.

Currently, minimally invasive total knee arthroplasty is defined as an incision length of < 14 cm. However, the length of the incision is not the primary influence on potential postoperative benefits to the patient and should not be the only characteristic of the minimally invasive approach for knee arthroplasty. Some other factors that should also be included in this definition are: 1. The amount of soft-tissue dissection (including muscle, ligament, and capsular damage). 2. Patellar retraction or eversion. 3. Tibiofemoral dislocation. Minimally invasive surgery should not be considered to be a cosmetic procedure but rather one that addresses patients' concerns with regard to postoperative pain and slow rehabilitation. Standard total knee arthroplasties provide pain relief, but returning to activities of daily living remains a challenge for some individuals, who may take several weeks to recover. Several studies have demonstrated long-term success (at more than ten years) of standard total knee arthroplasties. However, many patients remain unsatisfied with the results of the surgery. In a study of functional limitations of patients with a Knee Society score of > or = 90 points after total knee arthroplasty, only 35% of patients stated that they had no limitations. This finding was highlighted in a study by Dickstein et al., in which one-third of the elderly patients who underwent knee replacement were unhappy with the outcome at six and twelve months postoperatively. Although many surgeons utilize objective functional scoring systems to evaluate outcome, it is likely that the criteria for a successful result of total knee arthroplasty differ between the patient and the surgeon. This was evident in a report by Bullens et al., who concluded that surgeons are more satisfied with the results of total knee arthroplasty than are their patients. Trousdale et al. showed that, in addition to concerns about long-term functional outcome, patients' major concerns were postoperative pain and the time required for recovery. Patients undergoing total knee arthroplasty have specific functional goals, such as climbing stairs, squatting, kneeling, and returning to some level of low-impact sports after surgery. Our clinical investigations demonstrated that the minimally invasive surgical approach reduces hospital stays, decreases postoperative pain, and decreases rehabilitation needs as well as enables patients to return to normal function more quickly. It is important for surgeons to take an evolutionary, rather than a revolutionary, approach when performing minimally invasive total knee arthroplasty. The surgeon should downsize incisions progressively to prevent severe damage to the quadriceps mechanism. Extensive open exposure, prolonged patellar eversion, and dislocation of the tibiofemoral joint should evolve into a vastus medialis muscle split with patellar subluxation, retraction but not dislocation of the patella, and avoidance of gross dislocation of the tibiofemoral joint. Developing the techniques of minimally invasive total knee arthroplasty may be difficult and time-consuming, but patient benefits and satisfaction should outweigh the extra effort required. These changes require well-designed clinical studies to further document their effectiveness.

Arthroplasty, Replacement, Knee↗
PubMedDate not supplied

[The patella and the femoro-patellar joint during rheumatoid polyarthritis].

The authors report 2 series of cases of rheumatoid arthritis, one prospective of 115 cases, the other retrospective of 72 cases, and note the frequency of clinical and radiological patellar and femoro-patellar involvement during this disease. Signs of active rheumatoid disease in the patella were present in 31 cases. The most common lesions of the femoro-patellar joint space are narrowing and lateral dislocation of the patella. The femoro-patellar lesions evolve in parallel to the femoro-tibial lesions, but dissociation is possible. The early detection of a femoro-patellar syndrome permits effective treatment by isometric rehabilitation of the quadriceps. On the most advanced lesions, and when pain is limited to the femur and patella, an operation of reaxation of the patella may provide remarkable functional improvement.

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↗